Talk:Hard disk drive/Archive 5

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Archive 1

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Archive 3

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Bias in measurements

As a tangent to the endless "discussion" about the use of standardized computer units on Wikipedia, User:Centrx is using this section to try to push a POV that hard drive manufacturers should have marketed their devices using binary quantities, and that their use of decimal quantities is deliberately misleading. (See User talk:Centrx#Hard drives.) In other words, they're deliberately mislabeling their 80,000,000,000 byte drive as "80 GB" to inflate the actual capacity. (Since, by golly, everyone knows that the operating system reports it as "74.5 GB". ZOMG I've been ripped off!) I've pointed out quite a bit of evidence that hard drive measurements, when abbreviated, have always been abbreviated in a decimal way, that the decimal meaning was the one used by engineers long before they even invented these devices, and that the binary meaning was never standardized, de facto or otherwise. So there is absolutely no reason to expect them to switch to the non-standard binary units, and there is no reason to assume that they are using the standardized units in a deliberately misleading way. The hard drive manufacturers have explicitly stated their position. Without evidence of malicious intent (like a leaked internal memo or the like), there is no more reason to suspect other motivations behind this than there is to suspect that the Titanic was intentionally sank for the insurance money.

In CMOS, FDISK, Windows File Manager and Windows Explorer, my IDE disk reports smaller capacity than the number of bytes reported by CHKDISK. Why?
Because there are two different definitions of a megabyte and a gigabyte. Hard disk drive capacity is calculated by taking the number of Cylinders x Heads x Sectors x 512 bytes per sector. Hard disk drive manufacturers define a megabyte as equaling 1,000,000 bytes and CHKDSK calculates based on this value as well. However, your system's CMOS, FDISK, Windows File Manager and Windows Explorer calculate disk capacity based on a megabyte equaling 1,048,576 bytes. Therefore different utilities might report different capacities for the same drive.
— FAQs - Fujitsu

My computer shows less drive capacity than on the drive box label
Hard Drive Manufacturer Capacity Definitions
The listed capacity is an unformatted (raw) capacity. After partitioning and formatting, actual storage capacities may vary depending on the operating system and configuration. Maxtor adheres to the National Institute of Standards and Technology (physics.NIST.gov) definition of Megabyte and Gigabyte.
Examples:
1 MB = One Million Bytes

1 GB = One Billion Bytes

Operating System and BIOS Capacity Definitions
Storage devices are marketed and sold in terms of decimal (base 10) capacity. In decimal terms, one Gigabyte (GB) is equal to one billion bytes. Most BIOS’s follow this definition as well. However, many operating systems use the binary (base 2) numbering system. That would be two to the thirtieth power, or 1,073,741,824 bytes equals one-Gigabyte.
According to the NIST standard, an 80 GB hard drive would contain eighty billion bytes. 80,000,000,000 bytes divided by 1,000,000,000 bytes equals eighty decimal Gigabytes. In binary terms, 80,000,000,000 bytes would be divided by 1,073,741,824 for a total of 74.5 binary GB. However, there are still 80 billion bytes on the drive in either case.
— Personal Storage 3000DV: Installation Guide - Maxtor

Surely Western Digital cannot be blamed for how software companies use the term “gigabyte”—a binary usage which, according to Plaintiff’s complaint, ignores both the historical meaning of the term and the teachings of the industry standards bodies. In describing its HDD’s, Western Digital uses the term properly. Western Digital cannot be expected to reform the software industry. (Apparently, Plaintiff believes that he could sue an egg company for fraud for labeling a carton of 12 eggs a “dozen,” because some bakers would view a “dozen” as including 13 items.)
— Defendant Western Digital Corporation’S Brief In Support Of Plaintiff’s Motion For Preliminary Approval - Western Digital

Since this inflation hypothesis has led to lawsuits against the drive manufacturers, it should actually be mentioned here in more detail than it is. — Omegatron 16:40, 3 June 2007 (UTC)

platter sizes and form factors

"The names refer to the width of the disk inserted into the drive rather than the actual width of the entire drive."

This is not entirely correct. For example, so called 3.5" drives typically have 95mm platters—which is closer to 3.7". (3.5" is about 90mm).

I would like to see a small table of the sizes, with specific measurements, in both measurement systems. —überRegenbogen 02:03, 4 July 2007 (UTC)

See Form Factor Comparison Note there are several different diameter disks used in 3.5 inch form factor drives. I believe this is unique to 3.5" Tom94022 02:32, 5 July 2007 (UTC)

Operations per second

I'm not sure there is any agreement on "operations per second" since can be a strong function of block size but, be that as it may, there is at least one publication that has a modern drive at 561 ops, well above the numbers cited in the article. Accordingly I deleted the statement BTW there are standard tests of IOPS in the unix world but they mainly apply to storage subsystems and not individual drives. If anyone knows of a valid reference and wants to cite such, it would be a useful addition. Tom94022 17:11, 10 July 2007 (UTC)

FYI: answers.com copies this page..

http://www.answers.com/topic/hard-disk-drive-1

The table on disc interfaces looks "quite similar" .. :-) Oh btw, I made that table asfair. Electron9 07:07, 16 July 2007 (UTC)

Read Answers.com and read Wikipedia:Mirrors_and_forks/Abc#Answers.com. It is normal for Wikipedia to be copied if the license is closely adhered. ~a (user • talk • contribs) 13:57, 16 July 2007 (UTC)

I know about the license. Guess I've seen some bad behaviour from about.com in the past. And this kind of makes it obvious that they don't really have any content of their own. Also it has implications for public presence. Electron9 12:44, 18 July 2007 (UTC)

Disk Rotation Speeds

Why do manufacturers all use the same rotation speeds? 7200,5400, 10200 etc I can't imagine they all use the same motor manufacturer or do they?

Why isn't one of them busy Marketing there drive as being 7800 RPM instead of just 7400 for those really on the move etc!

Years ago, there were drives with speeds we'd see as odd now. 3200, 3800, 5800, 6300, 14400...eventually the market settled on 4500, 5400, 7200, 10k and 15k for the sake of clarity. The first three are fractional multiples of 3600 RPM, an artifact of now-ancient drives that ran their spindles directly off the AC mains (they used synchronous motors, and mains frequency in the US is 60 Hz, so they spun at 60 revolutions per second -- 3600 RPM). Since 3600 was something of a standard when the first small drives came out in the early 1980s, it stuck, even though the electronic servos they used could theoretically run at any speed. 10k and 15k are nice round numbers (even multiples of 1000). -lee 18:11, 10 September 2007 (UTC)

Physical interfaces on 1.8" disks

The section "Hard disk drive characteristics" states: "A previous 1.8" HDD standard exists, for 2–5GB sized disks that fit directly into a PC card expansion slot." Shouldn't this ideally describe that two previous standards exist. Apart from PCMCIA and ZIF there is also one commonly used with it's connector on the long side of the drive. Search for HTC426060G9AT00 to see an example of it. 213.114.65.148 13:24, 22 July 2007 (UTC)

SMD and IPI-2 harddisks missing completely

This wikipedia article is missing several (still used) harddisk types like SMD and IPI-2 (there might be several others but can't remember their names at the moment). Adding these would improve quality of this page quite a lot. Simakuutio 07:15, 9 August 2007 (UTC)

May I suggest the place for such additions, if at all, is the History Of Hard Disk Drives page not this page. SMD already has a page and probabaly should be cited and linked in the 1970's section - u might want to make such an addition. I'm not sure IPI-2 rises to a level sufficient for inclusion in any article; there were many such interfaces that IMO never achieved sufficient technical or market success to justify inclusion in any Wikipedia article. Tom94022 17:35, 9 August 2007 (UTC)

Number of platters

Updated from 2 to 3. IBM DTCA-23240 2.5 inch HDD (3.2GB (binary)), produced september 1998. had 3 platters (just disassembled). I assume, more recent HDDs can have more than 2 platters as well. -Yyy 16:09, 8 August 2007 (UTC)

SCSI = Small Computer "Serial" Interface

It's become popular to rewrite history by saying that SCSI stands for Small Computer System Interface, but the second S actually stands for Serial.

One can understand the confusion - after all, SCSI uses parallel data transfer, not serial data transfer. The name comes from the fact that devices are connected in a series along the cable (though not in series electronically - the devices are independent, and won't all stop working if one burns out, like some strings of tree lights). --Thanny 11:11, 16 August 2007 (UTC)

I believe that Alan Shugart disagreed with you; if I remember, I'll check my reference material tonight.

Atlant 12:54, 16 August 2007 (UTC)

I am looking at the cover of the ANSI X3.131-1986 "small computer system interface" specification; in its forward it acknowledges its origin in the "Shugart Associates System Interface" circa 1982. I personally attended many of the early SASI/SCSI meeting and never heard or saw the usage of "serial" in the context of either SASI or SCSI. BTW, Alan Shugart had nothing to do with SASI or SCSI, he left Shugart Associates long before SASI was conceived.Tom94022 15:46, 16 August 2007 (UTC)

Can we add a quote or some info on how precise hard drives are?

I don't think this article's "technology" section quite captures just how amazing hard drives are. To shorten a quote from Scott Mueler's Upgrading and Repairing PCs (17th Edition):

“

...to such a scale, the heads in this typical hard disk would be about [...] equal to the Sears Tower if it were tipped over sideways. These skyscaper sized heads would float on a cushion of air that to scale would only be 5mm thick (about 0.2") while [...] circling the earth once every 5 seconds!

”

I don't think this quote specifically is needed, although I enjoy it's accuracy (I can give someone more detail about it in IM where I don't have to worry about copyvios) and proper sense of scale. I think an explanation of how precise the mechanisms are is important --Lu c id 14:49, 16 August 2007 (UTC)

Anyone? --lucid 08:34, 29 August 2007 (UTC)

it's a great quote. it's short enough that, properly cited, it wouldn't be a copyright violation to add it. go for it, i say. Anastrophe 15:38, 29 August 2007 (UTC)

I'm not sure it is a reasonable analogy and I'm pretty sure Scott Mueler is not qualified to originate it. I once asked an aeronautical engineer (phD) working on flying heads what was a reasonable analogy so he came up with one based upon scaling the lift pads of a slider to the wings of a 747, something like a 747 flying 1/8" off the ground at 2k mph. He scaled holding the Mach number constant. That slider flew at about 10 times today's flying heights. The other analogy I've heard is kicking a football in the SF Giants ball park and having the ball come down between the goal posts in NYC's Polo Grounds (every 30 msec or so :-). Great quotes, but not of the quality that belongs here. Suggest u look for a quote from a disk drive technologist and not a journalist. Tom94022 01:18, 30 August 2007 (UTC)

There is one in Magnetic Storage Systems Beyond 2000 By George C. Hadjipanayis but it is copyrighted so unless u want to fight the fair use wars u will have to get permission to use it. His numbers are neither Mueler's or mine :-)Tom94022 01:28, 30 August 2007 (UTC)

It's not a matter of who wrote it, just the size comparisons. any analogy is going to vary based on what scale is used, and what hard drive it is based off of. --lucid 11:34, 2 September 2007 (UTC)

drive limits

Shouldn't this article mention something along the lines of : http://www.tldp.org/HOWTO/Large-Disk-HOWTO-4.html#ss4.2

?  —Preceding unsigned comment added by 70.55.86.204 (talk) 22:01, 3 September 2007 (UTC)

Should the history section mention Winchester?

Because I was referred here after searching for 'Winchester drive' (as many 'old guys' know this drive), should one not mention 'Winchester' in the history section? Topics on the floppy disk and mini-floppy disk acknowledge the role of Burroughs in Scotland, and no one ever called these 'Glenrothes disks'. Geologist 22:36, 1 November 2007 (UTC)

I don't think so; the history section is quite truncated and given the size of this article, IMHO, rightly so. Winchester is mentioned in footnote 1, covered in more detail in History of hard disk drives article and still more detail in Early IBM disk storage article. That's probably enuf Tom94022 02:56, 2 November 2007 (UTC)

I was also disappointed to see a lack of discussion of any disk technology prior to approx 1998. Mini & Mainframe systems (eg: DEC, IBM) from the 1950s onward had all sorts of interesting disk hardware. 208.62.177.45 (talk) 14:47, 29 May 2008 (UTC)

Name one :-) Actually, you make a good point regarding the History of hard disk drives article, but when I think about it there really were no significant non-IBM disk drives until the late 1960s. Since the early IBM drives are covered in their own articles, the only candidates that come to mind are the Memorex 630 (aka DEC RP01) - first significant non-IBM HDD and the CDC 9760 SMD -first non-IBM media. When I have a few more moments I'll add them. I suppose we could add Bryant as a curiosity. There were also several fixed head disk drives and drums, but that is another article. Tom94022 (talk) 15:09, 29 May 2008 (UTC)

Performance of competing technologies

I'd like to see a proper summary of the competing technologies - these are actually very badly covered in the individual technology sections of Wikipedia as presumably they are written by people who favour each technology. I've worked for 3 storage vendors all of whom displayed little honesty or knowledge in this area generally preferring the "what we have and more expensive is best" line to performance and reliability discussions. Comparisons SCSI, SAS, Fibre Channel, SATA. SSD

Here is my view of the performance and comparison criteria requirements to truly asses disk technology

1: Reliability - The single most important thing unless you have server level redundancy.
2: Performance under load when 80% full (Read and Write) - everyone runs their disks nearly full - and the newest and most accessed stuff is nearly always near the middle of the disk. Main cause for “my laptop used to be great and now it sucks.” syndrome.
3: Raw transfer speed - Like top speed in your car – oft quoted rarely used.
4: Hot swapability - important for servers and storage systems - can I unplug the disk without interrupting my business and how often does it work.
5: Performance when empty - a few people run lots of large disks empty to maximise performance for the rich and ungreen
6: Length of cable possible - Not normally important
7: Power consumption
8: Heat - normally related to power consumption but a big problem for people who buy 10K disks for their home systems.
9: disk rotation speed - together with how full the disk is probably a key performance indicator - but 10K and above disks don't survive well in uncontrolled environments.
10: Relationship of components - or why having a 2.4 Ghz CPU and a 5400 RPM disk do nothing for either performance or power consumption in your laptop.
11: Interface cheating. - More common than you think - a vendor needs to offer a new technology but doesn't have the technology today so puts on an interface converter - or converter chip on the disk. Voila your ATA disk is a SATA disk but with a negative not positive performance impact.
12: Operating system support. Almost always when new disk technologies are introduced .Example NCQ - the operating system dids not support it. And the first release drivers are always flaky. And then the drivers reveal a problem in the hardware so release 2 hardware comes out.
13: Chipset/Bios support - see above but for the PC or Server hardware
14: Who owns the technology -Is it a licensed technology - this generally affects the price and initial quality. Licensed technologies generally have better initial quality because the specification is controlled not interpreted - the "open/free" technologies generally better later in the cycle. Licensed technologies are almost always more expensive to implement. Firewire and USB are great examples of this cycle.
15: Price
--CDXP 11:19, 10 November 2007 (UTC)

Add to this list an important but always understated element of perceived performance: access time. Compared to drives of the early 90s, today's readily available hard drives are on the order of 10000x bigger and transfer data 50x faster, yet access time has only about doubled. A marginal increase in access speed will pay a much greater dividend than even a sizable increase in capacity or bandwidth to the average consumer who cannot fill a 750GB drive even if he sets out to do so. Whelkman (talk) 17:58, 23 November 2007 (UTC)

It's not for us to decide how HDDs should be judged. Any list of features we'd compare drives by would have to come from some cited, commonly referenced source. Anything else would be possibly tainted by our personal views, and fall under WP:OR. --A D Monroe III (talk) 15:30, 27 November 2007 (UTC)

It is a valid point though, access times are incredibly important, and that fact can easily be made out not to be subjective, through linking to comparisons between gaming load times etc. It just needs to be mentioned anyway, and the surprising development that well, there is no development, access times still suck. This is why SSD's are interesting, or rather one of the reasons.Talrinys (talk) 22:16, 18 December 2007 (UTC)

Capacity and access speed

I made an edit in this section that was a citation of a source proving the statement "throughput increases, which themselves have not kept up with growth in storage capacity." It was reverted immediately as link spam. The cited page is http://www.mattscomputertrends.com/Time.html. Its my page and research. The editor looked at the page for all of 12 seconds, according to the logs. I think the page is legitimate proof of the statement which otherwise has no cite. Due to my COE here (its my research), I want other opinions please. Matt21811 (talk) 09:23, 21 November 2007 (UTC)

Here's my two cents. Like you say, you're trying to include research that you wrote and it's your page, so there is an obvious conflict of interest in including this information. What's more, the research hasn't been published by any reliable sources so it's considered to be original thought. There's a little more info in the "Advertising and conflicts of interest" section that says that "You should avoid linking to a website that you own, maintain or represent, even if the guidelines otherwise imply that it should be linked." ~a (user • talk • contribs) 12:56, 21 November 2007 (UTC)

i'm the editor who reverted the addition. your page says that all data came from Storage Review. SR is a WP:RS. your site is not. furthermore, by your own post above - you seem to understand part of the issue - it's original research. so i'm not sure why you would have made the edit in the first place, knowing that it fails at least one criterion for inclusion. Anastrophe (talk) 15:54, 21 November 2007 (UTC)

He does absolutely have a point so, what we're looking at is a way to document it? A rather simple comparison would be the time it takes to fill up a harddrive now compared to maybe 10 years ago? That would be straightforward and undeniably accurate Talrinys (talk) 22:42, 7 January 2008 (UTC)

The caption for a picture is way too long

The picture of an HDD without the platter has a caption that is way too long. I was thinking if I should make it into a new section with the picture and a short caption? 21:46, 8 February 2008 (UTC)

agree, I think we can strike the caption in its entirety since much if not all of it seems to be covered in the paragarph or is too much informationTom94022 (talk) 22:36, 8 February 2008 (UTC)

This is an encyclopedic article, so let's be careful when contemplating 'striking' information. Are we going to lose anything? Is everything the caption states really covered elsewhere? Daniel B. Sedory (talk) 17:49, 10 February 2008 (UTC)

Changed! As near as I can tell the only thing added was the copper motor coils & bearing so I left it in. I changed the term disks to platters to agree with the sketch above, most of what was said in the caption is in the sketch above and in the text of the article. If u find anything in the caption that is not in the article, I suggest it goes in the article. Tom94022 (talk) 19:02, 10 February 2008 (UTC)

instaling widows

can instaling and uninstaling windos all the time damage your hard drive?eg 4 in two month.from KHATHU —Preceding unsigned comment added by 164.151.129.37 (talk) 11:13, 13 March 2008 (UTC)

Yes, that's an interesting question... My 6 years old Quantum 30GB got its sound very little changed after one reinstallation of Windows 2000 3 years ago. Scandisk found one bad sector and it seems that the heads are seeking slower than before (I have defragmented it before and after that reinstallation and I am absolutely sure that this is not caused by fragmentation). I don't know if anyone else have noticed but my drive is making a little louder noise when the computer is running Windows 2000/XP than when running Windows 98 (and more louder when running Linux) although I use the same software and open the same files. Although after 3 years my drive is still working normal without new bad sectors, I think that the question about wearing the actuators of a drive should be taken seriously, not only when reinstalling Windows, but when defragmenting and choosing which operating system to run. Unfortunately it is difficult to find any information on the Web about drive wearing... Are there any experts who can help? --Lefter 13:01, 8 April 2008 (UTC)

Screwed Up Captions

The captions in the "Integrity" section clearly do not refer to the pictures they're attached to. They should be changed by someone who is familiar with the significance of the two images. —Preceding unsigned comment added by 128.36.126.120 (talk) 21:53, 23 March 2008 (UTC)

I’m also not familiar with the significance of the two, but if the pictures are in no way in reference to the integrity section then it should be changed.--DavidD4scnrt (talk) 10:04, 25 April 2008 (UTC)

Turning a drive too soon after shutdown can damage its heads?

I had a misconfiguration problem with my BIOS and my computer used to turn itself back on as soon as it has shut down. I heard that turning on a hard drive too early (<5 sec) can damage the parking mechanism and the heads. Is that true? During the same couple of months, my drive (Quantum 30GB, bought 2001 y.) started seeking irregularly slow (it was defragmented) and I replaced it with a new to avoid losing data. But I couldn't repair my BIOS settings soon after I bought the new drive. Has the turning on caused a little wear/damage to the new drive? It's model is Seagate Barracuda 160GB (ATA 100 variant), SMART currently reports that the Spin Up time is 97 (all other values are 100, except Seek error rate, which is 69, but I hear this is normal for new Seagates)... --Lefter 13:30, 8 April 2008 (UTC)

Highly unlikely, but possible that frequent power cycling would damage heads/disks. Drives are tested thru 10's of thousands of such cycles. In PC's, typically nothing happens until the power supply decays, then the drive dynamically brakes (using stored energy in the motor if necessary) to stop quickly. If the power supply doesn't decay to zero before it starts up again, a badly designed drive might have problems with the transient voltage of the power supply but it would typically lock up rather than damage the heads. It is not just the PC's drive that will have problems in such a situation. I always let my PC set for a few seconds after a "Bill Gates" moment.

Yr defragmented drive with long seek times was possibly experiencing "heroic" error recovery - the drive had errors and never gave up until it corrected them :-). Sometimes this is spot related and u can cure it by surface scan and deallocating the spot, but if the drive is more than a few years old, it's probably time to upgrade

Tom94022 (talk) 16:44, 8 April 2008 (UTC)

Wrong image caption

The article contains the following image:

The caption is mistaken. No disk platter or mirror-like disk are visible. AxelBoldt (talk) 19:53, 14 April 2008 (UTC)

The caption is correct, the gray, mirror like surface is a portion of a disk. The reflection of the underside of the supension is clearly visible - e.g. note the two holes. Tom94022 (talk) 20:37, 14 April 2008 (UTC)

I believe that's not right. What you see there is two read-write heads and no mirror-like surface at all; the platter would ordinarily be situated between the two levers (one head writes on one side, the other writes on the other side), but the platter was apparently removed for the picture. It might appear like a reflection because the upper lever looks just like the lower lever; both have two holes and cables attached to the actual read-write heads. If it were a true reflection of a single lever however, you wouldn't be able to see the full length of the lower cables. AxelBoldt (talk) 15:53, 15 April 2008 (UTC)

at first i was going to agree with you, then i looked a while longer and became convinced it was indeed a reflection, then after doing some visual processing on the image (primarily increasing brightness) i believe you're correct. if you turn up the brightness, you can see two areas on the lower arm, offset to the left and down, where light cast from above is hitting the lower arm through the two holes in it. if it were a reflection, it wouldn't look like that. i think the neutral gray background that smoothly darkens across the image gives the impression of a reflective surface, but it's a false impression. Anastrophe (talk) 03:04, 16 April 2008 (UTC)

Well, I just emailed the photographer and he said "Yes, the caption is correct. The picture shows one head resting on the disk surface, and its reflection. You may notice that the wires to the head are arranged in exactly the same way in the reflection." I guess that settles it. About the two bright spots you found: they can also result from the reflection. Light passes through the two upper holes, gets reflected off the disk, forms to bright spots on the underside of the upper arm, and we see the reflection of this as the upper side of the lower arm. AxelBoldt (talk) 14:16, 18 April 2008 (UTC)

yep, i kind of thought that about the reflections but dismissed it. the thing with the wires is, since they're all done by machine, i figured there was a very good chance that they always look just like that, with virtually no variations. but a reflection it is, so, its settled! Anastrophe (talk) 01:26, 24 April 2008 (UTC)

Lead Image

I changed the image to this one (Image:hard disk platters and head.jpg) that I took specifically for WP use with the aim of providing a good illistrative image whilst I had one in pieces and it's been reverted with the explanation that it doesn't show the reflection. I am interested in more information as to why. The image does show a reflection, it clearly shows the reflection of the arm, which really is much clearer that the distorted hand reflected in the other image. Also, I would say that the new image is a much clearer representation of the disk in use with the arm on the head rather than being disassembled with a screwdriver. Furthermore it shows more components of the hard drive - it shows multiple platters, arm, head, static magnet, PCBs, head park and thus has higher enc value for an article on the complete hard disk? Your thoughts? Mfield (talk) 15:47, 25 May 2008 (UTC)

I agree that your picture is far superior. Furthermore, the reflection in the original illustration is at best irrelevant. Tom94022 (talk) 21:58, 26 May 2008 (UTC)

Good, I am not going mad. I am changing it back. If someone wants to revert, they can provide a better justification here. Mfield (talk) 22:03, 26 May 2008 (UTC)

Physical Mounting Position

Thanks to the authors for such an informative article. There is one question, the answer to which may be obvious to everybody else, that needs stated definitively. Can a modern hard drive be mounted in any position? On an oblique angle? In extremis, suspended temporarily from its cable? The answer to this could be handled in a single sentence, though I do not really know the answer. Thanks again, WPHyundai (talk) 15:59, 15 June 2008 (UTC)

In general I suspect the answer is yes for modern drives, other than on the string, but you will have to read the manufacturer's specification to get a specific answer and even then it might be vague. Here is a quote from a better written specification:

"7.5.4 Drive mounting

The drive will operate in all axes (6 directions). Performance and error rate will stay within specification limits if the drive is operated in the other orientations from which it was formatted.

For reliable operation, the drive must be mounted in the system securely enough to prevent excessive motion or vibration of the drive during seek operation or spindle rotation, using appropriate screws or equivalent mounting hardware." [HGST 7k500]

Note the above says why a string is not such a good idea. Also note the above is ambiguous about between axes. The reason I think the general answer is yes is that modern drive mechanisms are generally well balanced in all axes and the servos will take out any residual static biases. Vibration and recoil would be a problem on a string. Early drives were not well balanced. Tom94022 (talk) 17:39, 15 June 2008 (UTC)

Browsing Slow with Larger Drives?

I recently cloned my old 10GB hard drive to a 160GB drive - it was the smallest that I could find.

I note that the faster drive runs Windows much quicker but that browser load times are now longer.

I am told that this is characteristic of moving to larger drives, though I rarely see the matter stated in this context. If this is the case, is it not better to encourage quite small, fast drives for browsing rather than giant ones? Can anybody please shed light on the matter? I thank you, WPHyundai (talk) 16:17, 15 June 2008 (UTC)

Makes no sense to me, perhaps yr local Internet cache just needs to be filled. Unless Windows does something silly with placement of its files, your existing 10G should only fill 1/16 of the new drive, implying more data under the arms without seeking (even if the new drive has fewer heads), a higher data rate, and a shorter stroke (access time) to existing data - all of which means things should run faster not slower. But if you have to download a lot of stuff into yr local cache it will seem slow for a while and be dependent upon yr network data rate, not your drive data rate. Tom94022 (talk) 17:48, 15 June 2008 (UTC)

Cheap power supply unit can slowly kill a hard drive?

Here in small (8 million) Bulgaria, some low level repair specialists are spreading this rumor, based on some unofficial statistics. But none of them even explains what does it mean to supply an "unhealthy" electrical current to a hard drive? They just say that you should not buy some models of power supplies. Is it the constant voltage or its boundaries which make one model of power supply better than other? The page contains a link to a site discussing hard drive myths, but I think this site is written by a lowest level expert who considers only the case with burning a drive by too high voltage. Can anybody give a more complete explanation? Excuse me for the poor English. --Lefter 23:03, 25 June 2008 (UTC)

Disk drives are hard to kill and they monitor their supply. I'm not sure what are the characteristics of a cheap power supply but one of them might be poor output regulation which, in turn, might mean the drive detects an over/under voltage condition and parks its heads but then detects everything OK and returns to normal. Drives are rated for 50,000 or more such cycles but in such a hypothetical situation a drive might "slowly" fail over time due to excessive cycles (called load/unload or start/stop cycles). But you should hear the cycle. Also there might be weird voltage during the power on as the cheap supply tries to ramp up, this in turn might cause multiple cycles. In countries where power is expensive, turning your system off when not in use may be more common and a "cheap power supply might also cause excessive cycles during the power on cycle. Again you should hear the cycle. Just guessing a hypothetical cause, I doubt if short of way overvoltage that a power supply can kill a drive. Tom94022 (talk) 18:29, 21 July 2008 (UTC)

What does the sound of a drive depend on?

I know that some drives provide acoustic management options to slow the speed of the heads and reduce noise. But I have a drive with acoustic management disabled and another which does not support acoustic management (according to the program Hard Disk Sentinel v2.10). They both produce a little louder/sharper noises when I use Windows 2000 or XP, than when I use Windows 98 SE. The sounds are even sharper when I run Ubuntu or SUSE Linux. I am used to listen to the sound of my drives and I am sure this is not caused by fragmentation, opening different documents or something of the kind. Is it caused by more optimized/faster or bad for the drive/worser system software? I am worried that NT based Windows-es and Linux can shorten the life of the head actuators! My older 30 GB drive got its sound little changed after one reinstallation of Windows 2000 (during the installations it used to make the sharpest noises) and started seeking somehow slower. I know this can be caused by the disk surface which can have weak/problematic sectors. Scandisk found two neighbouring bad sectors over 1 GB from the end of the drive. Hard Disk Sentinel currently reports that there are 74 automatically reallocated sectors. But I bought a new drive (Seagate 160 GB), exactly a year ago, and installed Linux on it as a second OS. During the time I used the Linux, the Seek Error Rate SMART value was 61 (below the average limit of 63, according to SpeedFan 4.32 online analysis). I have heard that new Seagates have low Seek Error Rate values. But when I stopped using Linux and worked only with Windows XP, the Seek Error Rate value started slowly increasing and is now 71. To be short: Are Linux and NT based Windows unhealthier for hard drives than Windows 98 SE? Is there a way to tune Windows XP or Linux so that the hard drive produces "softer" noises as with Windows 98 SE? Lefter 18:30, 21 July 2008 (UTC)

See High frequency of load/unload cycles on some hard disks may shorten lifetime for one example of how a Linux OS can systematically change noise (and failure rate). It would make sense that excessive start/stop (or load/unload) cycles caused by poor choices in sleep mode parameters would cause noise and degrade a drive. Once such problems are eliminated, I doubt if there is anything about Linux or NT based Windows that is "unhealthy" for HDDs. If there are systematic noise differences between OSs, I suspect they have to do with caching and paging policies (more and/or longer seeks) but there is nothing unhealthy about seeking, per se; start/stop, on the other hand, is stressful. Tom94022 (talk) 18:54, 21 July 2008 (UTC)

New Study Finds U.S. Consumers Continue to Amass Valuable Troves of Digital Content

[1] --Kozuch (talk) 10:56, 10 July 2008 (UTC)

3.5-inch full-height?

I've got a few old manuals from the late 1980s and early 1990s describing 3.5-inch full-height (or near full height - 1.66") hard drives. Worthy of a mention? Rilak (talk) 09:05, 21 July 2008 (UTC)

IMHO, not worth mentioning, but if you have the time and a scanner, you ought to consider donating copies to Bitsavers. Email aek at bitsavers dot org if you can help Tom94022 (talk) 18:04, 21 July 2008 (UTC)

I mean the form factor, not the induvidual hard drive models themselves. As for me donating the manuals, considering that I got them from Manx, the search engine for old computer manuals, I think everyone has access to them already. I think the table in this article, which is missing these form factors, is misleading - it gives the impression that all 3.5-inch hard drives are half-height and that is simply not true. Rilak (talk) 06:21, 22 July 2008 (UTC)

Is this in reference to Hard_disk_drive#Form_factors? If you are trying to point out a distinction between 1.625" and 1.66" I wouldn't bother. My recollection, without any research is the "standard" HH vertical dimension was 1.625" nominal and there was a tolerance, so 1.66 would likely fall into that range or at most be a minor variant.

If this is is reference to the table in Hard_disk_drive#Capacity_and_access speed then I would footnote the maximum number of disks, probably 8 to 10, much like footnote 21 for the 5¼" HH. Tom94022 (talk) 16:37, 22 July 2008 (UTC)

Hmm... it now seems that there is some misunderstanding here... All the manuals I have from DEC seem to refer to this "half-height" (1.66"+) as full height and 1.0" as half-height. I actually didn't see the section you pointed me to as well... Rilak (talk) 06:21, 23 July 2008 (UTC)

Both links work on my machine.

Section 3. Form Factors has bullet for 3.5" which states the 1.63" dimension.

Section 2. Capacity and access speed has a table at the bottom that gives the current maximum capacity and number of disks by form factor.

DEC is not what I would call an authority on HDD nomenclature, they marched to their own tune. Originally HH was used in the 5¼" form factor for 1.625" height disk drives, floppy and HDD, it was precisely ½ of the 3.25" full height drives. The early 3½" FDD and HDD were mainly 1.625" high, some people called them HH using the 5¼ terminology and meaning 1.625" and some called them Full Height (FH) or Standard Height. I think most of the OEMs eventually adopted HH = 1.625" as the common usage and Slim Line for 12.5 mm or 1". Again I wouldn't mention it in 3. Form Factors and I doubt if any DEC product would set an upper limit for disks in Section 2. Capacity and access speed so at this point my recommendation is to drop it. Tom94022 (talk) 06:42, 23 July 2008 (UTC)

Nah, I meant that for some reason (probaly from staring at the computer screen too much + playing too many games) I didn't notice the section you pointed me to in the article that mentions that there was once 3.5-inch 1.6"-height hard drives. I also didn't intend to add an entry for DEC, but one for the 3.5-inch 1.6"-height form-factor, which I did not see was mentioned in a sort of hard to see sentence in a section I didn't notice. Rilak (talk) 07:22, 23 July 2008 (UTC)

OK, there have been many z height variants in 3½-inch and below; IMHO, too many to bother increasing the size of the table in section 2. Capacity and access speed to accommodate all of them. But I would footnote the maximum number of platters in a 3.5" 1.63" z height much like footnote 21 for the 5¼" HH. I seem to recall it being about 10 and when I have the time, I'll do some research to see what I can find. Tom94022 (talk) 19:28, 1 August 2008 (UTC)

Drive Motor

perhaps the article should mention what kind of motor (AC/DC, Unipolar, Disktype etc) is used in HD ? HH 15:09 (CEST) 30 July 2008 —Preceding unsigned comment added by 145.254.95.134 (talk) 13:08, 30 July 2008 (UTC)

Form factor, etc. table

Although current 2.5" drives probably top out at 3 platters (I don't keep track), a couple past 2.5" drives that have 4 platters are the IBM Travelstar 3XP (17 mm height), and Travelstar 32GH (12.5 mm height).

See: http://www.hitachigst.com/hdd/support/dlga/dlgades.htm / http://www.hitachigst.com/tech/techlib.nsf/products/Travelstar_32GH (Page 3 of the datasheet.) —Preceding unsigned comment added by 70.231.232.26 (talk) 07:18, 17 August 2008 (UTC)

Faster drive, air drag?

The article states: "Drives running at 10,000 or 15,000 rpm use smaller platters because of air drag and therefore generally have lower capacity than the highest capacity desktop drives."

This claim isn't cited in the article. But I'm not an expert by any means so I'm wondering if anyone could clarify the factual accuracy of this claim. My initial impression is that the inertia of the platter, and not air drag, is why faster drives have smaller platters and thus lower capacity.

It's been a while since I flipped through my physics books, so I could be off. Can anyone verify this? —Preceding unsigned comment added by 208.65.221.154 (talk) 19:51, 3 September 2008 (UTC)

15K rpm HDDs, 10K rpm HDDs, and desktop (5400 rpm)HDDs all use the same size disks: 3.5" in diameter. The size of the motor changes to increase rotational speed. Mobile HDDs (laptops) use 2.5" disks, iPods and GPS use 1.8" disks, and for a while there was a 1" diamter disk for the IBM/Hitachi Micordrive. --Hollisterbulldawg (talk) 20:19, 12 September 2008 (UTC)

Wait - the article says the 10K and 15K rpm HDDs use smaller platters due to air drag. Are you saying their platters are the same size, and only the motors are bigger? —Preceding unsigned comment added by 208.65.221.154 (talk) 21:15, 19 September 2008 (UTC)

The platters in the higher rpm 3½" drives are smaller than the industry standard 95mm disk[2] used in 7200 rpm (and earlier lower rpm) HDDs. The issue is the heat generated by the work required to overcome the windage[3]. Today I think these higher rpm 3½" drives all use the industry standard 65mm disk[4] used in 2½" drives, but I seem to recall that some of the earlier higher rpm drives used disk diameters in between the two, e.g. 90mm. Tom94022 (talk) 16:54, 11 October 2008 (UTC)

There seems to be something important missing here...

How do hard drives work?

So far the only place the article seems to touch on this is under "integrity". What are platters, what are they made of, how is data represented on them, whats a read/write head, how does it read and write data on and off the platters, etc etc etc. 76.15.173.124 (talk)

Yeah, I think this is a problem with the article. I read the "Integrity" section and then became curious about exactly how they worked but couldn't find anything. Seems to be quite an important thing to mention. --137.195.250.2 (talk) 06:00, 13 September 2008 (UTC)

"Hardware information"

I don't believe anything in this edit is worth keeping. It's trivial information, unsourced, and seems to focus on negatives. It would appear obvious that plenty of previously-common configurations are no longer produced, much as with any other type of old PC hardware. Chris Cunningham (not at work) - talk 00:26, 10 October 2008 (UTC)

Agreed, and it is now gone Tom94022 (talk) 16:56, 11 October 2008 (UTC)

2.5" laptop drive ATA connector

I don't see anything saying or describing ATA laptop connector. It is different that 3.5" hard disk connector because it is also used to provide power. That is why I believe it should be also added to the page.

There are a whole bunch of different connectors used in HDDs varing by form factor (3⅛, 2½, 1.8, smaller) and interface (ATA, many SCSIs, FC, SATA/SAS, others), probably way more than 10. I don't see any described in the article so why single out just this one? Tom94022 (talk) 17:05, 11 October 2008 (UTC)

Software

I am thinking of starting a new section in this article entitled "Software", which will list the various software tools for hard disk drives, as at present there is currently no mention of such software tools in the article. Once the list is big enough, it can be split off into it's own article. It's possibly that a comparison table may be more appropriate. I am also aware of the various lists out there covering these software titles, including List of disk partitioning software, List of backup software‎, List_of_defragmentation_software, List_of_disk_imaging_software and Data_recovery#Recovery_software. Considering many of the listed applications do more than one task and there aren't that many titles in total, the plan would be to merge them into one more manageable list or table. Please agree or disagree --Hm2k (talk) 12:38, 7 November 2008 (UTC)

As a step in the right direction I have created a new category entitled Category:Hard_disk_software, this can be added to anything related to the subject, a list can follow. --Hm2k (talk) 17:29, 11 November 2008 (UTC)

Is anybody aware of software that can make a hard drive physically inoperable, to the level of not being reusable by low level formatting, partitioning etc?

e-mail hacking

Recently, we let an employee go. All week I have noticed that my computer was shut down completely. (which i never do) I was logging into my e-mail and the employee that we let go, his info was automaticly up there! My question is: How can I determin if this ex-employee was actually in my office USING my computer and going into my quick books? I veiwed his history as he was already logged in by email...it showed all the sites that he visited, but is there a certain place i can get verifacation of the dates and ip address from when and where he used his e mail??? I'm hoping he wasn't in this office Laura —Preceding unsigned comment added by 24.44.164.252 (talk) 18:56, 13 November 2008 (UTC)

This is not a general discussion forum and your question has little to do with hard disk drives. Ask on a relevant newsgroup or other discussion forum. CrispMuncher (talk) 18:59, 13 November 2008 (UTC)

This is a page for discussion about improvements to this article. You need to ask your question at the relevant Reference Desk instead. Mfield (talk) 19:01, 13 November 2008 (UTC)

How many primary and logcal driver can make of a hard disk

Sir, my problem it that i want to make more than 30 partitions of a hard disk (two 250GB HDD) how can i mange it please send the procedure on my id night_14thmoon@yahoo.com i anybody can help me —Preceding unsigned comment added by 203.99.191.64 (talk) 06:30, 21 November 2008 (UTC)

This page is for discussing improvements to this article only. You should ask your question at the Computing Reference Desk instead. Mfield (talk) 06:38, 21 November 2008 (UTC)

SSDs

Perhaps somethign needs to be said about SSDs and similar technology. This could be a short sentance and a link to the SSD article. But they are growing in importance. 82.2.15.100 (talk) 11:08, 19 December 2008 (UTC)

It's a good idea, but despite their growth, SSDs aren't eating HDs' lunch quite yet. I think we should give it another year before SSDs are mentioned on this article. Jogar2 (talk) 18:25, 3 February 2009 (UTC)

I suggest it is a bad idea! SSDs are another article, like tape drives, optical drives, floppy disks, etc. They can all come together in Computer_storage. If in the unlikely event SSDs obsolete HDDs, then it would be useful to so mention such a cause of the demise with an appropriate link to the SSD article. In the meantime don't clutter this article with SSDs. Tom94022 (talk) 00:05, 4 February 2009 (UTC)

hard drives

I have a 80gb hd, 120 slave what is the value —Preceding unsigned comment added by 76.112.133.120 (talk) 00:43, 17 January 2009 (UTC)

Drive value (and anything else for that matter) can be determined by searching completed listings on Ebay. The short answer: very little. Jogar2 (talk) 18:22, 3 February 2009 (UTC)

New 2 TB drive

It's been reported that Western Digital is releasing this month the new 2 TB drive, model WD20EADS. One of the sources (do a Google search and you will find more replying the same news): http://en.expreview.com/2009/01/13/western-digital-to-launch-2tb-hard-drive-this-week.html —Preceding unsigned comment added by 189.70.23.128 (talk) 09:24, 17 January 2009 (UTC)

Fast and slow parts of the disk

Hello there! I was just wondering if either the beginning or the end of a disk would be inherently faster and what kind of differences are we talking about there? (In practice you probably would want you OS or swap partition there.) 78.27.75.173 (talk) 13:08, 19 January 2009 (UTC)

Take this with a grain of salt, but assuming uniform bit density I'm guessing that the edge of the disk would be faster to access, since it contains more bits and so a partition of the same size would have a smaller radius and so the head would move a smaller distance on average between any two random points in the partition. Dcoetzee 21:32, 19 January 2009 (UTC)

The outer edge does have faster read times, but that is balanced by slower seek times. here is a nice link on the subject. - MrOllie (talk) 21:37, 19 January 2009 (UTC)

Dcoetzee has it right for the outer edge of an HDD!

I don't know where MrOllie (or IBM) gets the idea that the average seek time varies much by radius because in my experience that is not true. The seek times are strictly a function of the distance moved! It doesn't matter where you start from nor for that matter which direction you move. The average seek time is then a function of how many cylinders there are in the physical domain - the time to seek 1/3 the cylinders is a reasonable approximation of the average seek time within that domain. If you partition, as IBM talks about, the average seek time in the partition will be less than the drive's average seek time over all cylinders, because there are fewer cylinders. Note that if the partitions are all the same size in GiB, the outer most partition will use the fewest number of cylinders and therefore have the lowest average seek time of all the partitions. It is well established in SAN/NAS world that short stroked drives are one solution to a performance problem and that the preferred location is towards the Outer Diameter to take advantage of the higher data rate which is typically about 1.5 times the Inner Diameter data rate.
What is true is that if you have some object you go to often and its not too large, e.g. a directory map, it might be a good idea to place it in the center of its partition, because the worst case seek is then at most 1/2 the number of cylinders. However if the object is large, the higher data rate towards the OD may be more important. And if you go to it often, why isn't in main memory :-)

Tom94022 (talk) 23:05, 19 January 2009 (UTC)

Thank you for all this interesting info and the useful link! --85.131.24.56 (talk) 19:12, 10 February 2009 (UTC)

AFR and MTBF

Once the drive product is in production, the more valid [citation needed] metric is annualized failure rate (AFR). AFR is the percentage of real-world drive failures after shipping.

According to the AFR article, the AFR is calculated from the MTBF. It seems to me that this would *not* make it more valid. Instead, it would make it more useful. 206.53.197.24 (talk) 22:32, 22 January 2009 (UTC)

From a user's perspective perhaps the most useful metric would be actual Annualized Return Rate; unfortunately it is not specified by the HDD vendors nor is it generally known until it is too late :-( The vendors specify either MTBF or AFR (Annualized Failure Rate), which can be related but are not of too much use unless u are in a dispute over warranty issues. The data unfortunately suggest that some models do not meet their specified AFR and/or specified MTBF. Also note that the no trouble founds are reported as high as 43% Tom94022 (talk) 23:57, 22 January 2009 (UTC)

Error: Transfer Rate

"Data transfer rate (as of 2008) at the inner zone ranges from 45 MB/s to 3.0 GB/s, while the transfer rate at the outer zone ranges from 74.0 MB/s to 111.4 MB/s." The 3GB/s figure is incorrect; these numbers are disk-to-buffer rates, not buffer-to-host. 3GB/s (GigaBYTES per second)is way too high these days. The author probably meant 3Gb/s (gigaBITS/sec), or roughly 300MB/s, which is the buffer-to-host rate for the "SATA 3Gb/s" standard (and still about 4x too high for the maximum inner-zone transfer rate.) I expect the correct maximum for the inner zone is around 75 MB/s. If I can find a reliable source I'll correct it. Anybody know of such a source? I'm off to check Seagate and Western Digital for some datasheets but I haven't found much in the past that details disk-to-buffer rates, probably because they are much lower than SATA interface speeds. Steve Hyland (talk) 05:07, 24 January 2009 (UTC)

That's nothing but a 3-month bad edit that was never caught (diff). The original number was 74.5 MB/s, in line with your estimate. It looks like you fixed it anyway. Dcoetzee 01:46, 5 February 2009 (UTC)

Hard Disk problem for open it

I am facing a proble in my hard disk when i am open my c drive it ask me open with command So if you have any solution to resolve it then please let me know earliest my email id is: ssonu277@rediffmail.com —Preceding unsigned comment added by 59.99.13.75 (talk) 07:42, 27 March 2009 (UTC)

Removal of a {{fact}} tag

This edit is inappropriate. Any statement which isn't trivially obvious should be referenced by a reliable source. Our readers are not to be expected to dig up their own references on Google. The {{fact}} tag should go back in. Chris Cunningham (not at work) - talk 08:48, 13 April 2009 (UTC)

Anyone who has flown on a commercial airplane and observed the many users of PCs with HDDs would agree that it is trivially obvious that ordinary hard drives can safely be used in flight. If however, the disputed fact is the altitude of the airplane cabin is limited then the tag is misplaced. Either way it should not be where it is and we all have better things to do than sprinkle fact tags about. Tom94022 (talk) 22:15, 13 April 2009 (UTC)

I agree with Chris Cunningham that Tom94022's edit is inappropriate. It looks like Tom94022 is bullying the other editor with 3RR when edit warring himself to make an edit that does not improve the article. Tom94022 you need to remember to cooperate with other editors and not bully or harass them with wikilawyering.Glider87 (talk) 07:25, 14 April 2009 (UTC)

The first edit that did not improve the article was attaching a fact tag to a trivially obvious statement. Furthermore it is a statement that can be readily verified by a simple google search as stated in my comment. The second edit that did not improve the article was the unsigned-in editors reverting without comment. If any of u really cared about the quality of the article you would check out the fact and, as I did, take off the fact tag as trivial or add in a reference. Maybe even put a dispute tag on the sentence and discuss it here, wherein it would become obvious that the statement is trivially obvious; but instead who is wikilawyering? Tom94022 (talk) 16:16, 14 April 2009 (UTC)

The placement of the fact tag is correct and your edits did not improve the article. If it is so "trivially obvious" then you should have put a reference instead of removing the tag. If you cared about the quality of the article you would not try to bully other editors while revert warring. Stop trying to wikilawyer and bully other editors by threatening them with 3RR when your edits are correctly reverted. Glider87 (talk) 00:43, 15 April 2009 (UTC)

I would appreciate any factual basis for your apparent contention that the statement in dispute is not trivially obvious. I have stated one basis and pointed to another. You seem instead to be wikilawyering rather than dealing with the issue. May I remind you, as stated at the start of this section, that we should:

   * Be polite
   * Assume good faith
   * Avoid personal attacks

* Be welcoming

FWIW, my reminder about 3RR was my attempt to help an anonymous user avoid an easy trap. Your calling it bullying seems to me to be both a lack of good faith and a personal attack. Tom94022 (talk) 21:26, 15 April 2009 (UTC)

It is not up to me to provide a "factual basis for your apparent contention that the statement in dispute is not trivially obvious" because you are making a claim that it is "trivially obvious" and that someone should "try a google". You made the claim you have to support it. Since you have still not replaced the tag with a valid reference, despite being challenged to provide a reference and having several days to do so and given your continued comments here you cannot claim to be offline, then your lack of valid reference demonstrates that it is not as trivially obvious as you claim. Your own inaction refutes your claim. Regarding your block quote. First we have your completely inappropriate revert [5]. Secondly there is your threatening and bullying comment [6] when you are actually edit warring. That is also demonstrating you are failing to assume good faith and how you are not being welcoming. Thirdly we have your comment "If any of u really cared about the quality of the article" which is a personal attack by you towards three editors, is a failure of assuming good faith, also you're not being welcoming and not being polite. You are not following any of the points you have included in your block quote which demonstrates how you are wikilawyering by trying to cite behaviour guidelines when not following them yourself. You are completely at fault here Tom94022. You have two editors telling you so much and still you continue to make inappropriate edits here. Glider87 (talk) 05:20, 16 April 2009 (UTC)

Agree 100% with Chris Cunningham (not at work) and Glider87. Tom you really need to calm down and correct your behaviour to something more expected by Wikipedia. This is not some internet forum where someone can score points by playing up to the crowd and being disruptive. Fnag aton 13:55, 16 April 2009 (UTC)

No one yet has presented any facts to rebut my statement above that:

Anyone who has flown on a commercial airplane and observed the many users of PCs with HDDs would agree that it is trivially obvious that ordinary hard drives can safely be used in flight.

No one (except me) has done any research to validate that the statement is trivially obvious. Instead what is presented are ad hominem arguments of little use to anyone. Tom94022 (talk) 20:06, 16 April 2009 (UTC)

Again. Your lack of valid reference demonstrates that it is not as trivially obvious as you claim. Your own inaction refutes your claim. You have still not provided any valid reference so you are still wrong. Glider87 (talk) 14:57, 17 April 2009 (UTC)

Again, Gilder87s fails to present any facts that justify the need for a reference but instead appears to just prefer wikilawyering of little use to anyone. I contend that the universal usage of laptops containing HDDS in pressurized commercial aircraft without warning by either the aircraft operator or the laptop manufacturer is sufficient to make the statement "trivially obvious." Glider87 has provided no evidence to rebut this fact observed by anyone using a commercial aircraft. It really is simple to find support, as for example in Failure Mechanisms In Electronic Products At High Altitude and elsewhere. But it really shouldn't be necessary to justify the obvious to a wikilawyer. Now that I have given a reference will Gilder87 remove the fact tag? I wonder. Tom94022 (talk) 04:00, 18 April 2009 (UTC)

Tom, the bar for inclusion of information on Wikipedia is not what you contend but rather what you can demonstrate by including relevant references. Glider87 is correct to point out above that you have not provided any valid information so what you contend be on its own cannot be used in the article. Also you cannot say "Google for it" and expect that to be good enough to except something to be in the article. Read WP:RS because it explains why your actions are completely wrong here. The fact that it has taken you so long to provide any reference goes to show how what you think is trivially obvious is actually not that trivially obvious. By the way, I could for example provide a reference like Warp drives in use today and claim it supports something I said. Obviously just providing a reference on its own is not good enough because you have to show what part of the reference is relevant to the specific text in the article. For your actions to be correct you should have removed the tag in the article and placed the reference you now claims to support what the article text says. What you did instead was to disrupt the article and edit war and wikilawyer. You need to learn to behave properly on Wikipedia because this is not the first time your bad behaviour has caused problems here. Fnag aton 04:51, 18 April 2009 (UTC)

An ad hominem attack by Fnag, a probable Sock Puppeteer, adds nothing. There has yet to be posted anything as to why the sentence in question is not trivially obvious and therefore requiring neither a reference nor a fact tag. It does Wikipedia no good to clutter articles with trivial references. Tom94022 (talk) 18:07, 20 April 2009 (UTC)

You are making ad hominem attacks because you incorrectly used harassment and bullying tactics against an editor who correctly placed a fact tag then when you were told to stop being disruptive you then resorted to writing lies about editors. The sentence in question is not trivially obvious and the placement of the fact tag is correct. You have not posted anything to support what you have been claiming and the burdon of proof is against you to support what you claim. What you are doing is known as an Argument from ignorance where you claim your premise is true only because it has not been proven false when actually you have not proven your premise to be true in the first place. With regards to the sock pupper accusation you have just made I saw this on Thunderbird2's user page and I have to say your posts are very similar to Thunderbird2. Given your very similar posting style to Thunderbird2 I think it is very likely you have been using more than one account to bully and harass others so you cannot speak with any authority on this subject. The tactic you have employed on the report page above is to waffle until it becomes too large to read and with that tactic you escaped being blocked. That is the tactic you appear to be employing now because you you have been shown to be wrong so you now waffle on irrelevant subjects to divert attention away from your mistakes. However what you are now doing is being disruptive because you know you are wrong yet you refuse to admit it. Glider87 (talk) 18:37, 20 April 2009 (UTC)

An ad hominem attack by Glider87 adds nothing while actually making an argument from ignorance. There has yet to be posted anything as to why the sentence in question is not trivially obvious and therefore requiring neither a reference nor a fact tag. It does Wikipedia no good to clutter articles with trivial references or discussions with ad hominem attacks. Tom94022 (talk) 01:01, 21 April 2009 (UTC)

Tom by repeatedly misrepresenting other editors you are being disruptive and harassing them. The fact is there are three editors who are telling you why what you did is against Wikipedia policies and there is nobody supporting what you did. You have not posted anything to support your unfounded claims either. I also note that now you have contradicted yourself because you have been using ad hominem and now you admit that Wikipedia does not need you cluttering up this discussion. Also Glider87 is correct because you are trying to use the logical fallacy linked above. Since your position is just a logical fallacy then it is weak and can be disregarded. So the tag in the article stays until someone can provide something like a valid link and argument for why it should be used. Fnag aton 19:10, 21 April 2009 (UTC)

I don't believe I have misrepresented anyone. Fnag; however, clearly misrepresents me when applies my statement about "articles" to this "discussion" and when he states I have "not posted anything to support your unfounded claims." Finally, Fnag is just incorrect when he alludes to "a logical fallacy" which I think he means to be an Argument from ignorance; in this case I have both made an argument as to why the statement is trivially obvious and pointed to a reference that confirms the truth of the statement. Fnag et al's failure to respond in any way other than with ad hominem attacks suggests they are either ignorant or wikilawyering. Either way, not helpful. Tom94022 (talk) 23:33, 21 April 2009 (UTC)

I see at least two misrepresentations posted by Tom94022 "No one (except me) has done any research" and "If any of u really cared about the quality of the article". Not to mention the bullying and harassment by threatening 3RR when Tom94022 was edit warring. Fnagaton is correct because you have not posted anything to support your unfounded claims. Fnagaton did not allude to a logical fallacy because I posted the link to the Argument from ignorance logical fallacy. If Tom94022 reads and understands the Argument from ignorance link then Tom94022 will see exactly how his point of view is making a claim and then failing to support it while also claiming because nobody has "refuted" what he stated then it must be true. Tom94022 made a claim but did not support it with anything like a valid argument and that means other people do not have to refute what he stated because he has not provided anything worth refuting. Tom94022 has still not posted anything worth refuting and is now being disruptive by harassing and misrepresenting other editors. Glider87 (talk) 18:03, 22 April 2009 (UTC)

I agree it should stay. If "it is a statement that can be readily verified by a simple google search" then there shouldn't be any problem finding a reliable source for it. I don't buy the "obvious" argument either. In any case we mustn't fall into the trap of assuming modern Western (or at least developed world) standards are universal. For instance, there are still a few DC-3 Dakotas in scheduled airline service in Africa. Not pressurised. Such an aircraft can and probably will exceed the maximum operating altitude of many hard drives. CrispMuncher (talk) 21:21, 21 April 2009 (UTC)

Thanks for pointing to some evidence, but I hope you noticed that the sentence in question presumes pressurized aircraft so the DC3 example is not particularly relevant nor is it biased. BTW, DC 3 Operating altitude: 10,000 ft (3,048 m) is more or less the HDD specification. There is no problem finding a reliable source, I have pointed to one. I just think the sentence in question is trivially obvious and therefore does not require a reference much less a fact tag. So I won't put a reference tag on the line. I will however respond to misinformation and/or misrepresentations in this discussion as they occur. Tom94022 (talk) 23:33, 21 April 2009 (UTC)

That makes four editors who are telling Tom94022 his claim is wrong. Tom94022 has still not posted anything like a valid argument. The conclusion is that the statement is not trivially obvious, so Tom stop being pointy and admit you are wrong so you can move on from your disruptive tactics. Glider87 (talk) 18:10, 22 April 2009 (UTC)

Yet another ad hominem attack by Glider87 adds nothing while actually making an argument from ignorance. Other than ChrispMuncher's rebutted statement, nothing posted to date provides evidence as to why the sentence in question is not trivially obvious and therefore requiring neither a reference nor a fact tag. It does Wikipedia no good to clutter articles with trivial references or discussions with ad hominem attacks. BTW, since when is discussion disruptive? I have to point out that four lawyers thought waterboarding wasn't torture, so I'm not sure what credence to place upon attacks by two ignorant wikilawyers. Tom94022 (talk) 19:03, 22 April 2009 (UTC)

Stop harassing and personally attacking me. Stop being disruptive. You have not rebutted anything ChrispMuncher has written and you have not provided any valid argument. You are not "dicsussing" you are using personal attacks and disruptive tactics. A case is point is how you keep on copying the fallacious ad hominem and argument from ignorance when actually you are the person who is using ad hominem and argument from ignorance tactics. Glider87 (talk) 19:12, 22 April 2009 (UTC)

Yet another ad hominem attack by Glider87 adds nothing while actually making an argument from ignorance. Tom94022 (talk) 20:22, 22 April 2009 (UTC)

The above comment demonstrates Tom94022 will not stop harassing me and being disruptive. Tom94022 has still not posted anything like a valid argument. Four editors are now telling Tom94022 that the tag is correct but Tom94022 is still being pointy and disruptive. Glider87 (talk) 20:31, 22 April 2009 (UTC)

To state that the above is yet another ad hominem attack by Glider87 adds nothing while actually making an argument from ignorance is neither disruptive nor harassment but merely stating facts. Furthermore, it is pointy of you to continuously state that I have not presented anything like a valid argument when in fact I have and you have failed to present any evidence that my arguments are not valid - you just don't agree with them. Tom94022 (talk) 21:10, 22 April 2009 (UTC)

Okay, Tom94022, stop causing disruptive edits and personal attacks. This is quite enough. Ginbot86 (talk) 23:52, 22 April 2009 (UTC)

I agree this is getting quite out of hand. Hopefully Tom94022 will listen and stop causing disruptive edits and personal attacks. I'm amazed he would try that instead of providing a valid argument. Glider87 (talk) 21:11, 23 April 2009 (UTC)

It is neither harassment nor disruptive editing nor a personal attack to point out that no editor, Glider87 in particular, has yet to respond to my valid argument as to why the tag is unnecessary nor has any editor commented on the valid reference I have provided. Instead what we get are ad hominem attacks, particularly by Glider87, that add nothing to the discussion. Tom94022 (talk) 00:09, 28 April 2009 (UTC)

You have not made any valid argument. You have made a claim and not suppported it. On the other hand we have the evidence that you have repeatedly failed to support your claim, thus demonstrating how the tag should remain since it is not trivial. You are using ad hominem, harassment and personal attacks because you know what you have posted here is wrong. As several posters have now said you must stop being disruptive. Glider87 (talk) 09:24, 28 April 2009 (UTC)

What Tom94022 is doing is known as an Argument from ignorance where he claims his premise is true only because it has not been proven false when actually he has not proven the premise to be true in the first place. Tom94022's refusal to provide any valid argument and use of harassment is not constructive and is disruptive, back away Tom94022 before you get blocked. Glider87 (talk) 09:59, 28 April 2009 (UTC)

Contrary to what Glider87 asserts:

I have made an argument; Glider87 not responded other than to say it is not valid.
I have supported my claim (or argument) with a link; Glider87 apparently has ignored it.
The history above is that Glider87 has not introduced any evidence other than ad hominiem attacks.

What Glider87 is doing is an argument from ignorance where he claims a premise is false only because it has not been proven to his satisfaction to be true. He disregards evidence that the premise is true. Glider87's refusal to provide any valid argument and his use of ad hominem attacks is not constructive. His threat to have me blocked is silly, but typical of his ad hominem tactics (bully, harrassing, wikilawyer, revert warring, disruptive, etc.) rather than honest discussion. Tom94022 (talk) 16:35, 28 April 2009 (UTC)

Tom, stop being disruptive. You have not many any valid argument because you have not supported any claims you made, actually you were challenged several times and failed to produce any valid evidence. The link you posted does not support your claim that the fact is "trivially obvious", actually the link you posted shows this is not a trivially obvious fact. An example of a trivially obvious fact is something like "clouds produce rain" or "the grass is green". Since you claimed only you had done any research on this topic but you repeatedly failed to produce any valid link over a reasonably long period of time of being called upon to do so then the conclusion is that your failure demonstrates the topic is actually not "trivially obvious". Glider87 has not been making ad hominem attacks, you have been using ad hominem and making personal attacks and harassing other editors. Also your claim "he claims a premise is false only because it has not been proven to his satisfaction to be true" just goes to show how ridiculous your point of view is. Firstly, Glider87 has not claimed what you just misrepresented. Secondly, it is perfectly reasonable to expect someone making a claim to have to support it because this is how a valid argument is made. You made the claim this fact is "trivially obvious" and since nobody here accepted your claim it is "trivially obvious" then you have to prove it is "trivially obvious" by providing valid evidence, proof and a strong argument. Since then you have not provided any strong argument and have not provided any valid evidence. Since you have failed to persuade anyone that your claim of being "trivially obvious" has any validity then you have only yourself to blame for providing no valid argument. You have also been told to stop being disruptive by several other editors and yet you have refused to do so. So again, stop being disruptive otherwise you will face sanctions from the administrators. Fnag aton 23:55, 28 April 2009 (UTC)

Stepping in to draw a line under this and prevent it from descending further...

Some thoughts on all of this...

The fact appears to be far from trivially obvious as evidenced by consensus, and as such it is fair to expect that it be backed by a citation.
The fact is not contentious or damaging to readers so there is no reason to remove the information in the short term, it can easily remain flagged as cite needed.
Consensus here is that the fact is not obvious and so the tag should stay. It is inappropriate to remove it against consensus.
Burden of proof is on the person supporting the fact to prove it, not on other editors or readers to be expected to know something.
Arguing against consensus and policy is disruptive, continuing an argument to such a degree over something so minor as a fact tact is unhelpful in the extreme.
I would say that the tag should stay until a cite can be found and if adequate efforts have been made and no cite can be found to back the claim then the claim should go until such time as a reliable source is added.

Mfield (Oi!) 00:25, 29 April 2009 (UTC)

Thank you. I hope Tom94022 will listen to this unbiased summary and concede that consensus is against his point of view and that the burdon of proof is on him to make a valid argument. Glider87 (talk) 05:24, 29 April 2009 (UTC)

Unfortunately Mfield apparently has not read my argument or examined my evidence but instead relies upon a purported consensus. Consensus requires discussion and so far there has been little discussion of my argument or evidence. Thanks to Fnag we know that

An example of a trivially obvious fact is something like "clouds produce rain" or "the grass is green".

Fnag doesn't say why these are trivially obvious facts but I assume it is because so many observers can validity these facts that it is not necessary to cite a reference to such facts. Similarly I claim this sentence is trivially obvious.

Note that modern commercial aircraft have a pressurized cabin, whose pressure altitude does not normally exceed 2,600 m(8,500 feet) - thus, ordinary hard drives can safely be used in flight.

because tens of millions (perhaps hundreds of millions) of commercial aircraft passengers in pressurized cabins have used or observed the use of laptops containing HDDs in flight without damage, warning from the flight operator of potential for damage or prohibition of such usage by laptop manufacturer or HDD manufacturers. ~~I have suggested that the fact tag could be moved to the altitude limitation of the sentence which to me is far less obvious than HDD safety in pressurized flight.~~ So far only one person has responded to this, citing the unpressurized DC3 which is not applicable. I also have provided a citation to an article that states in part that "Some typical hard drive specifications are: Max operating altitude 10000 ft ..." and "The unpressurized airborne environment will exceed the disk drive specification"[emphasis added] both of which agree with my contention that the sentence is trivially obvious. Fnag claims to have read this article but some how he finds, without citation, that the article "shows this is not a trivially obvious fact." It is not disruptive to ask for discussion, unfortunately I have to repeat this because most of what is above is assertions without evidence and/or ad hominem attacks rather than discussion. Tom94022 (talk) 18:26, 30 April 2009 (UTC)

I have withdrawn my suggestion about Cabin pressurization fact because I just realized the sentence in question is already linked to a supporting article. Tom94022 (talk) 21:15, 30 April 2009 (UTC)

Consensus arrives from discussion, there has been little dicsussion because you have not presented a valid argument to discuss. The consensus is that you have not presented a valid argument and the consensus is that what you have written has failed to persuade anyone here of your point of view. It is not disruptive to ask for discussion, but it is disruptive when as demonstrated above you revert war, use personal attacks, use ad hominem, harass other editors and keep on copying what other editors have written and use that to attack them. It is the first time you have posted anything like the explanation you have above, but the explanation still does not support what you have been claiming about the fact being trivially obvious. This is because it is trivially obvious that clouds produce rain and the grass is green because people in general can directly observe these things and it is widely known that clouds are made from wet stuff (or cotton wool or candy floss), but in general people know rain falls from the sky and that clouds carry rain. It is not trivially obvious to people that pressure has anything to do with harddrive operation because people in general do not know about the inner workings of harddrives, so do not know how pressure can affect drives and may also be unaware that modern aircraft operate on a pressurised system. It is because of this complex (to the general public) series of logical steps that the fact is by consensus deemed to be non-trivial. Speaking personally it is trivial knowledge for me, but articles are not written for me, they are written for the general public. So once again, post a valid argument to show why you think it is a trivially obvious fact for the general public. Fnag aton 02:43, 1 May 2009 (UTC)

Tom94022 it is not a good idea to accuse an uninvolved administrator of not reading your argument or evidence when it is obvious that you have not presented any valid argument or evidence that supports your claim. The conclusion is "the fact appears to be far from trivially obvious as evidenced by consensus" AND the "Burden of proof is on the person (you Tom94022) supporting the fact to prove it".Glider87 (talk) 04:41, 1 May 2009 (UTC)

How external interference could effect HDDs

I was reading through this article tonight, and realized that there was no real mention to how external forces (aside from air pressure, physical shock) can effect HDDs. Specifically: What would happen if someone put a strong magnet (ie like a 1 inch long magnet you put on a refrigerator) on the outside of the disk? Or for example if a strong EMP hit, say from a solar flare or coronal mass ejection? Or maybe a weapon is developed that can generate strong electromagnetic fields? Has anyone done any research on this?

It may seem a little "doomsday-ish", but one can't help but think that HDD's are really the only permanent large-capacity drives able to store data (Aside from certain optical discs in the works that aren't out yet), but they're magnetic -- but are they really safe from some of these external forces? I mean, so much of human kind's data is being stored on magnetic hard drives (Take Wikipedia as a prime example!) You hear of solar flares shorting out electronics in power grids, so why not hard drives? Imagine the panic if most of the HDDs (and therefore most other electronics) were wiped due to some disaster?

I'll do some web searching on the subject, but it might be interesting to include a few lines about in the article. —Preceding unsigned comment added by Cody-7 (talk • contribs) 08:28, 28 April 2009 (UTC)

HDDs are pretty tough, particularly with shock sensors to move the heads to a safe location. Regarding some other potential issues:

"Hard disk drive platters are mounted within a housing that in itself provide some amount of shielding to prevent a degaussing process from being effective. In our shop [now Seagate Recovery Services], we have exposed fully intact hard disk drives to very high levels of magnetic fields and have seen much or most of the data still intact on the device. The strength of any degaussing unit required to penetrate the Head Disk Assembly (H.D.A.) housing would probably cause considerable damage to any other diskette or magnetic media within several yards, perhaps even in the next room."[7]
Altitude is discussed in the section above, you can save your self a lot of reading by jumping to the end.
Since HDDs for the most part get their power from the systems power supply and are generally within metal enclosures they are fairly well shielded from solar flares. Put it another way, if a flare is big enuf to get an HDD then we have a whole bunch of other stuff to worry about like avionics, automobile electronics, TVs etc.

Tom94022 (talk) 21:30, 30 April 2009 (UTC)

Add link to http://en.wikipedia.org/wiki/Disk_buffer

Suggest adding this link, perhaps in the Capacity and Access Time section. I was puzzled when I found no mention of this topic.Therealdp (talk) 14:05, 17 June 2009 (UTC)

On second reading, this cross-ref might fit better in the Data transfer rate section. But I see no response, so I'm wondering: Has this suggestion been overlooked, or deemed unnecessary?)Therealdp (talk) 17:21, 19 June 2009 (UTC)

Been thinking about it (my buffer got full). How about just a linked new subsection under Other Characteristics, doesn't have to say much if anything, just link to the Disk Buffer article. About the only thing missing in the article is a comment about transfers from the buffer are at the I/O data rate and not the lower sustained data rate. Tom94022 (talk) 22:57, 19 June 2009 (UTC)

Suggest putting it first in the section, i.e., before Data transfer rate, because that subsection mentions "disk-to-buffer" transfer rate. I agree it would be best to keep it brief, to reduce the chances it will say something that (sooner or later) contradicts the link. Indeed, it would be a good idea for you to read that link first, if you haven't already.Therealdp (talk) 12:26, 20 June 2009 (UTC)

HDDs in avionics; loss of cabin pressure

I'm surprised that, apparently, ordinary HDDs are used in the avionics of pressurized aircraft if loss of cabin pressure can crash them. I'd think it would be mandatory to use drives that are immune to that eventuality. Am I reading something into the text that isn't intended?Therealdp (talk) 16:37, 17 June 2009 (UTC)

I don's see that the article says, "ordinary HDDs are used in the avionics of pressurized aircraft?" What it does say is, "Specially manufactured sealed and pressurized disks are needed for reliable high-altitude operation, above about 3,000 m (10,000 feet)." FWIW, the loss of cabin pressure will not immediately cause destruction so the HDD can be turned off and probably survive - the passengers will go long before the drive does. Tom94022 (talk) 15:58, 18 June 2009 (UTC)

You're right. Please excuse me for overlooking this as I reflected on what I'd read later (which is when I posed the question). I think what threw me is the sentence that follows the one you quoted: "Note that modern commercial aircraft have a pressurized cabin, whose pressure altitude does not normally exceed 2,600 m(8,500 feet) - thus, ordinary hard drives can safely be used in flight." I believe it could be improved a bit, and the issue I raised clarified, by changing the last part to "can be used safely by passengers in flight." Not an error or anything significant -- just a small suggested clarification.Therealdp (talk) 19:05, 18 June 2009 (UTC)

Not a problem, i liked yr suggestion so I made the change. At the risk of opening an old wound, do you think a citation is necessary at the end of the changed sentence or is it fairly obvious if the cabin is pressurized the drives can be used? :-) Tom94022 (talk) 00:40, 19 June 2009 (UTC)

This is a reminder to Tom that he must not violate WP:POINT and remove the fact tag because as the administrator says the burdon of proof is on Tom to prove it.Glider87 (talk) 12:01, 19 June 2009 (UTC)

It is "trivially obvious" to me that ordinary drives can be used safely at altitudes that exceed the manufacturers' specs by passengers in the cabins of pressurized aircraft. I think that debate was silly.Therealdp (talk) 17:15, 19 June 2009 (UTC)

I should have said "trivially obvious given the preceding text." The deduction could, however, be made even more obvious by noting additionally in the text that HDD manufacturers must assume a minimum ambient air pressure when designing their products and, understandably, use a value that supports human life and normal physiological function. It follows logically then that any artificial environment -- be it airplane, spacecraft, submarine, etc. -- that prevents asphyxia will provide the ambient air pressure needed to maintain a proper gap between the head and platter.Therealdp (talk) 12:17, 20 June 2009 (UTC)

The administrator already said it was not trivially obvious and so did everyone else. Just because a new user suddenly appears who just happens supports Tom doesn't mean the consensus has changed. The same argument applies, you have to WP:PROVEIT if you think it is trivially obvious by providng reliable sources. Tom failed to do that and that is why the consensus is against his point of view and that is why he has been warned about WP:POINT. Glider87 (talk) 15:14, 20 June 2009 (UTC)

I agree that it is trivially obvious given the previous text. I think this suggests a text change that can eliminate the fact citation. Glider87 likes to say there is consensus and that the arguments have been rebutted; so far he has not provided any evidence to rebut any argument, just conclusions and threats. Tom94022 (talk) 16:11, 20 June 2009 (UTC)

"Just because a new user suddenly appears who just happens supports Tom" You seem to be overlooking the fact that I've done more than express an opinion. I've demonstrated that the tagged sentence follows logically from other, unchallenged information in the preceding text. I've also shown how the logic can be clarified by providing additional information. (An added sentence should suffice.) If the conclusion is clear, no citation should be necessary and the tag should be removed. Therefore, if we wish to be fair and our primary interest is in improving the article, we should encourage Tom to propose an edit and seek consensus re. whether the new text eliminates the need for a citation.Therealdp (talk) 19:43, 20 June 2009 (UTC)

Tom the consensus from the administrator above is "the tag should stay until a cite can be found and if adequate efforts have been made and no cite can be found to back the claim then the claim should go until such time as a reliable source is added." - You have not provided any cite so the section is going to be removed until a reliable source is added. The same applies to you Therealdp, you have not provided any cite and it also doesn't matter if you think you have argued it logically or not, the fact is the burden of proof is against you and you have to WP:PROVEIT. It is simple, you have to provide reliable sources for claims. You have not done either of those things here. There has been more than enough time for Tom to to propose an edit but all Tom does is theaten and attack people instead. Glider87 (talk) 02:28, 21 June 2009 (UTC)

I'll put the case more explicitly: We know that A (adequate ambient air pressure) is necessary and sufficient to ensure B (proper head/platter air gap) is true. We also know that A is necessary (although not sufficient) to ensure C (neighboring humans breathing and healthy) is true. I've suggested adding a sentence explaining further that HDDs are designed so that "adequate" is the same for them and humans. Thus, if we know that C is true, A must hold and, therefore, B is also true. Do you not understand this reasoning, or is it that you understand but believe other readers won't? In either case, where do you believe the logic fails? Perhaps it can be clarified further.Therealdp (talk) 03:11, 21 June 2009 (UTC)

I underdstand because I have more technical knowledge than Tom but other editors won't understand because it is not trivially obvious and the adminstrator's comments also say it is not trivially obvious. Produce reliable sources to support your claims. The claims have been there with the fact tag for long enough and Tom has not produced any valid reliable source. So the claims get removed. I must now warn Tom that he must not edit against consensus. Glider87 (talk) 06:00, 21 June 2009 (UTC)

You haven't responded to my request to specify where the logic fails in the case I presented. That case requires no technical expertise WRT HDDs to understand, so even if your assertion that yours is superior to Tom's is correct, it's beside the point. As for the admin's comments, they and the consensus you speak of pertain to the passage you removed and are irrelevant to the present discussion, which concerns the development of a revision that will justify removal of the tag. If you are unwilling or unable to contribute usefully toward this development, you should withdraw from the discussion until a proposed revision is ready for evaluation. At that time, a new consensus can be sought.

Meanwhile, given that the passage was permitted to stand originally and was not edited at all, let alone in a way contrary to the admin's comments, you should restore it. The timing of your removal action smacks of petty vengeance and intellectual cowardice. That is, your behavior can be interpreted as an effort to thwart an improvement to the article that, for some reason you haven't specified, doesn't suit your tastes but you can't/won't argue convincingly against. Furthermore, you appear to be trying to put yourself in a position to accuse Tom of edit warring if he posts a revision. This conduct is unseemly and you should correct yourself.Therealdp (talk) 11:26, 21 June 2009 (UTC)

"You haven't responded to my request to specify where the logic fails in the case I presented." - That is not relevant because you have not demonstrated your claim by provding reliable sources. The threshold for inclusion of claims in articles is what you can show with reliable sources, not what you think or claim on the talk page. Don't you dare to even try starting with the personal attacks, Tom is wrong to try that and you are also wrong to try that. Since you resort to personal attacks instead of proving your claims with reliable sources that demonstrates that you are not willing to constructivly edit this article. I gave you several chances to provide reliable sources, you did not. I gave Tom even more chances to provide realiable sources he did not. You both use personal attacks and both just state what you believe without providing proof. You both act like you are the same person with the same agenda. Prove you want to improve the article by providing valid reliable sources. Until you and Tom apologise for your personal attacks you should be removed from this discussion and leave Wikipedia to those like me who work towards improving articles. Glider87 (talk) 12:17, 21 June 2009 (UTC)

I didn't intend a personal attack and regret that you took my remarks this way. I meant to alert you to the unbecoming ways in which your removal action can be interpreted. I apologize for offending you and encourage you again to reconsider what you've done.

Your statements about having to provide reliable sources for claims, etc., suggest you've missed the point of what I (and Tom, I believe) are trying to accomplish: Development of a revised passage for which readers will agree the previously tagged claim follows logically from undisputed facts. A revision that meets this criterion is not apt to be challenged and, therefore, will not need the tag or a citation. It is illogical to request a source when we're trying to eliminate the need for one.

I welcome any assistance you can provide in composing a revision that satisfies the objective I've described. A good way to start would be to either confirm the validity of the case I made or show how it can be clarified. That case can then be used as an outline and expanded into an improved passage. If you don't want to assist, though, I propose that we table this discussion and wait for Tom.Therealdp (talk) 20:45, 21 June 2009 (UTC)

My actions are to stop Tom from being disruptive. I have seen no apology from Tom, but I do see he is continuing to edit against consensus which demonstrates he is being disruptive. He has edit warred on this same topic before and he is doing so again. You have not provided any reliable sources to support your claims. The consensus is that reliable sources must be provided for the fact tags. The consensus is documented above. I have eliminated the need for sources by removing the offending claims until you can find some reliable sources for those claims. It is logical that you provide reliable sources for your claims. Your claimed validity is not relevant because you want to include claims that do not have reliable sources and that is contrary to WP:RS and contrary to consensus. It doesn't matter how longed winded you want to make the argument here because unless you can provide reliable sources it won't appear on the article page. Glider87 (talk) 22:28, 21 June 2009 (UTC)

Therealdp, sorry my question got u into this. As you can see, Glider87 is not interested in discussion; he is ignoring your analysis just as he ignored my argument and the citation i provided. There really has been little discussion, Glider just likes to fight. I find it particularly appalling his deletion of an entire paragraph which has pretty much been unchanged since 2006. So even thought it is against my principles to add a citation, I will add the one I provide - wonder what will happen Tom94022 (talk) 21:04, 22 June 2009 (UTC)

I am not ignoring any "analysis". I know how these drives work. I am saying that neither of you have produced reliable sources to support the claims you make. The PDf you link does not support your claim either Tom, that was the consensus from the last time you tried to be disruptive. Glider87 (talk) 23:07, 22 June 2009 (UTC)

It would have helped if you'd called attention promptly to WP:SYNTHESIS, which I discovered today at WP:VPP (and you referred to today in the other thread). That policy rules out the solution I advocated.Therealdp (talk) 04:03, 23 June 2009 (UTC)

Indeed. Tom does know about that policy though. Which is what makes his actions on this topic disruptive. Glider87 (talk) 04:49, 23 June 2009 (UTC)