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Wikipedia:Reference desk/Archives/Computing/2011 March 3

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March 3

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Mostly downloaded video file

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I am downloading a television program using utorrent. I am stuck at 97%. If I burn this to dvd as is, does this mean that the last 3% of the episode will be missing, or that I will see some flickers on the screen and some cracks in the audio because the download distributes the 3% error over the whole thing evenly, or will it just be no good at all or unplayable or what? I don't have DVD+RW so I don't wamt to waste a dvd to test it out if it has no chance of being decent to watch.--141.155.143.65 (talk) 01:06, 3 March 2011 (UTC)[reply]

Bittorrent clients don't (necessarily) download a file in order, from beginning to end. Instead they download it in chunks (often with different chunks coming from different peers, and sometimes downloading chunks from peers which themselves don't have a complete copy of the whole file). So a Bittorrent client like uTorrent has to piece these chunks together, and this often means that an incomplete download has a few missing chunks in all kinds of random places. I don't have uTorrent specifically to hand, but this screenshot shows a partially downloaded file, with the downloaded sections in blue and the missing sections in gray. So at best you'll get some bumps and clunks etc. when the player encounters the missing sections, but you may get nothing at all. Some media container formats are more tolerant of damage than others, and depending on where the missing chunks are you might get something that stops part way through, or doesn't play at all. -- Finlay McWalterTalk 01:19, 3 March 2011 (UTC)[reply]
Thanks. So I guess there's no real way to be sure short of just doing it.--141.155.143.65 (talk) 13:50, 3 March 2011 (UTC)[reply]
Sure there is. Try to play it in VLC, which can play DVD files that aren't burnt. --Mr.98 (talk) 14:49, 3 March 2011 (UTC)[reply]
or you could use a disk emulator like Daemon Tools. VLC is designed to be able to play rather damaged files, so you might be disappointed if you test in VLC and then burn the disk to play with a different player. With 97% of the file done you should probably be able to view the file, but this depends on format and exactly which part of the file is missing. Taemyr (talk) 20:37, 3 March 2011 (UTC)[reply]
I wonder if you couldn't try to stream it through VLC, convert it into some other video format, and then burn that to do the disk? If VLC would read it, it would probably output something with blank spots rather than empty sectors, which would make it more burn-able. But this is just a guess. --Mr.98 (talk) 12:45, 4 March 2011 (UTC)[reply]

how many gb is 5nb

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how many gb is 5nb —Preceding unsigned comment added by 202.88.229.22 (talk) 04:26, 3 March 2011 (UTC)[reply]

The prefix giga (normally abbreviated "G", not "g") means a billion, while nano (normally abbreviated "n") means a billionth, so that would be a billion times a billion or a quintillion (1018), making 5nb = 5 quintillionths of a Gb. However, the "b" part confuses me. Do you means bits ? If so, a billionth of a bit (or any fraction of a bit), is meaningless, as bits only exist in integer quantities. StuRat (talk) 05:04, 3 March 2011 (UTC)[reply]
In some contexts you can have non-integer numbers of bits. See Shannon entropy.
Suppose for example that you enter a lottery that you have one chance in a billion of winning. The next day, someone informs you reliably that you did not win. How much information is that? Not very much; you were pretty sure you wouldn't win. But it's some information. By Shannon's measure, about 1.4 nanobits. --Trovatore (talk) 05:29, 3 March 2011 (UTC)[reply]
Another thought, perhaps you had a typo and meant to ask "How many Gb in 5 Mb ?". In that case, we compare the giga prefix, meaning a billion, with the mega prefix, meaning a million, and thus there are 1000 Mb in a Gb, so 5/1000 of a Gb (or 1/200 of a Gb) in 5 Mb. This is complicated by the fact that computers often use multiples powers of 2, so that 1000 really is 1024. In that case, there are 5/1024 Gb in 5 Mb.
One last comment, "b" is used to mean a bit, while "B" is used to mean a byte, which is usually 8 bits. Case is very important when dealing with "GB", "Gb", "MB", "Mb", etc. The same is true of metric prefixes, where "M" = mega- and "m" = milli-. StuRat (talk) 05:16, 3 March 2011 (UTC)[reply]
Assuming that you made a typographical error, and actually intended to ask how many Gb is 5Mb; for decimal units the answer is 0.5%, and for binary units the answer is about 0.488%. Rocketshiporion 08:38, 3 March 2011 (UTC)[reply]
... and remember that disk manufacturers use decimal units, not Gibibytes. Dbfirs 09:17, 3 March 2011 (UTC)[reply]
... and that no one actually uses the word "gibibyte", because it's goofy. APL (talk) 15:20, 3 March 2011 (UTC)[reply]
Hear, hear, brother. Comet Tuttle (talk) 17:52, 3 March 2011 (UTC)[reply]
Powers of two, you mean. 213.122.68.101 (talk) 11:01, 3 March 2011 (UTC)[reply]
Yes, correct (and corrected). StuRat (talk) 05:29, 4 March 2011 (UTC)[reply]

Difference between Fab site and Assembly site

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I was looking at the list of Intel manufacturing sites, which is divided into two sections: Fab sites and Assembly/test sites. What's the difference in layman's terms between Fab and assembly? I was thinking in my head that maybe the Fab sites are where the engineers actually design new and more advanced chips and manufacture, on a smaller scale, chips on a scale intended to try out the designs, and that chips manufactured in the Fabs actually end up inside non-prototype, sold end products little or none of the time, while the assembly sites are where the bulk manufacturing of products designed at the Fabs takes place. Is this about correct? Thanks. 20.137.18.50 (talk) 14:45, 3 March 2011 (UTC)[reply]

For Intel, "fab" refers to semiconductor device fabrication. Assembly will refer to assembly of Intel products, such as Intel graphics boards. -- kainaw 15:31, 3 March 2011 (UTC)[reply]
Assembly also refers to assembly or packaging of the processor or other chip. The processor dies are fabricated in a relatively high tech site (traditionally for complex things like CPUs in places like the US, Germany, Japan although there's increasing interest in Singapore, Taiwan as well as UAE and China in gettingg fabs there), they're then sent on to be packaged into a procesor chip and tested in another relatively low tech site. If you look at the processor it will often have the packaging site [1] altho AMD has been putting both sites [2] for a while. If you're still confused, look at a processor without the heatspreader like [3]. The shiny bit is the actual die i.e. the actual processor that's fabricated in the fab site. Nil Einne (talk) 15:46, 3 March 2011 (UTC)[reply]
Thanks, Nil Einne. I see the "Diffused in Germany, Made in Malaysia" at [4]. It sure seems to be precarious though to be shipping naked dies halfway around the world. Those must be some special shipping containers and they must have to specially clean them before opening them in the packaging plant. 20.137.18.50 (talk) 17:12, 3 March 2011 (UTC)[reply]
While this is just a guess more then anything, I'm pretty sure they are shipped as entire wafers, i.e. the wafers are not cut into individual chips/dies until they reach the packaging plant. So this sort of thing is what's being shipped around the world (although they're not actually using that size yet). You may also be interested in [5] particularly page 4 although it doesn't say where the steps take place Nil Einne (talk) 18:36, 3 March 2011 (UTC)[reply]
I realise that many people posting here are not native English speakers, but you may be interested to know that, even with semiconductors, the plural of "die" is "dice".--Phil Holmes (talk) 18:41, 3 March 2011 (UTC)[reply]
"die - (plural dies)a device for cutting or moulding metal into a particular shape", Oxford Dictionary. 91.125.112.146 (talk) 18:54, 3 March 2011 (UTC)[reply]
"Dice" is only the plural for small usually cubic gaming items with markings on the sides. "Dies" is the plural for all other uses of the noun "die". -- kainaw 20:19, 3 March 2011 (UTC)[reply]
Taking the middle ground Die (integrated circuit) suggests we're all correct to some extent (well perhaps not the parts that imply one is exclusively correct) as both are accepted. Well what I presume is the ref to dice doesn't directly link to the supporting page but a search on Google Books does come up with other refs. Although perhaps you could also say we're all wrong since the article also says die is accepted and [6] suggests usage in the industry has evolved to that. Nil Einne (talk) 22:17, 3 March 2011 (UTC)[reply]
I used to work in the industry - I worked in a wafer fab clean room and was in charge of a packaging clean room - and we, and all the others I talked to in the industry, called them dice. I presume they were regarded as analogous to small gaming cubes - certainly not cutters. I agree that the plural of the cutting devices is dies. Just my 2p. --Phil Holmes (talk) 09:22, 4 March 2011 (UTC)[reply]
I worked in a similar area when I was on a contract a long time ago. We called them "dies". Some people thought we were saying "dice". When speaking, the sound difference between "dies" and "dice" is almost impossible to detect. Nobody knew anyone thought it was "dice" until one guy left a note in which he wrote "dice", resulting in a good two weeks of jokes at his expense. -- kainaw 13:58, 4 March 2011 (UTC)[reply]

Youtube video view milestones

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Hi, is there anywhere which has a list of YouTube video view milestones e.g. "first video to reach 100k?" And does anyone know the answer to my example? Thanks in advance. —Half Price 22:57, 3 March 2011 (UTC)[reply]

Why do I hear a door closing?

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I am at a library with Mozilla Firefox, one of only three libraries where I have sound.

Every once in a while I hear a door closing. It must be an ad, but I don't ever see the ad that is causing this.Vchimpanzee · talk · contributions · 23:41, 3 March 2011 (UTC)[reply]

I associate that sound with a friend having left the Instant Messaging area, so they are no longer available for chat. Do you have an IM running ? StuRat (talk) 04:07, 4 March 2011 (UTC)[reply]
Some program that is running has an alert set up to use the door closing sound (a standard system sound with most installs of Windows). Without knowing what is installed on the computer, it is absolutely impossible to know which program is triggering the sound and what event in that program is being used to trigger the sound. As usual - the library's IT staff is who you need to ask. -- kainaw 13:54, 4 March 2011 (UTC)[reply]
This is a little of a longshot, but it may be that someone has set up the computer to play this sound when certain "program events" occur. In Windows XP, try Start -> Control Panel -> Sounds and Audio Devices, click the Sounds tab, and you'll see a list of "program events" like "Default Beep" and "Device Failed to Connect" - if you select each one in turn, you'll notice the popup menu below says the name of the ".wav" sound file that will be played when that event happens. Clicking the triangle next to that will play the sound for you. By looking through all the program events you may find that someone has set up the door-closing sound to play when something common occurs. Comet Tuttle (talk) 17:42, 4 March 2011 (UTC)[reply]
StuRat has the right answer. I was signed into AOL to read emails. For some strange reason, that apparently means I'm signed into AIM as well, even though I don't participate. I've received instant messages without knowing why, but I can only conclude that being signed into certain sites makes me "available".Vchimpanzee · talk · contributions · 19:25, 4 March 2011 (UTC)[reply]
Resolved

StuRat (talk) 22:56, 4 March 2011 (UTC)[reply]