Wikipedia:Reference desk/Archives/Computing/2006 August 23

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iTunes Library Transfer

I'm moving into college and getting a new computer there, so I want to move my music library onto a portable hard drive. I opted to use an iPod, but just as a hard drive, by dragging from the directory where I keep my iTunes music library onto the iPod (not using iTunes at all, in the transfer.) However, while dragging some of the files, which are seemingly random, an error message says "Cannot copy file: Cannot read from the source file or disk." I am running Windows XP and the iPod is a never-before used 40 GB 4G iPod, but I don't think that should be relevant. The files, as far as I know play fine in iTunes. Thanks for any help! --ParkerHiggins ( talk contribs ) 02:37, 23 August 2006 (UTC)

Following up, I isolated one of the folders that was causing the problem, and it followed typical iTunes nesting format (i.e. Artist>Album>song.mp3) However, there were three seperate folders for this album: one which contained the songs, one which was empty, and one which, when I attempted to open it, gave me a similar error message to the one I received before. Still no info on how to work around it (without transfering file-by-file...) or why it's happening. --ParkerHiggins ( talk contribs ) 02:46, 23 August 2006 (UTC)

Try running chkdsk and checking the folder's ACL. --cesarb 11:51, 23 August 2006 (UTC)

I would recomend updating all the files in iTunes onto your ipod >USING ITUNES<. Then simply copy the files of your ipod onto your new computer. Copyin music from your ipod to your computer can be done by:- Opening explorer and unhiding files - this can be done by going to Tools>Folder Options. Then click the View tab. Goto the Hidden files and folders section and select "Show Hidden Files and Folders" Then click "OK". Once you have done this connect your ipod and go to its directory in explorer. ther should be a folder called iPod_Control (i've got a 5th generation ipod so i do not know if it is the same with older ipods). If i am wrong with the name of the folder then look for the folder that is a slightly lighter yellow than the others(now this depends on your theme- im doing these instructions using windows classic theme.)Once you found the hidden file go into it. Copy the "Music" folder to your computer. Best idea would be to put it in your music folder and then direct iTunes to it. You can stop showing hidden folders by undoing the above. That should have done it.

Well that was easy. almost the same answer i gave for iPod dysfunctional after connecting to Windows machine. Hope that helped -- JEZ

Can standard DVD players read DVD-DL?

I have a Core Duo Mac Mini which can burn dual layer DVDs. What I want to know is if most standard set top DVD players can play dual layer DVDs.

• Did you read Dual_layer_DVD#Dual_layer_recording? Recent machines can, it probably depends on the age of the DVD player in question. - Mgm|^(talk) 11:23, 23 August 2006 (UTC)

Probably. --Proficient 04:20, 24 August 2006 (UTC)

debug with modems in linux

Hi folks, I'm using Red Hat Fedora Core 3, with KPPP for my connection, and a fairly typical modem (I think) by Multi Tech Systems. Every time I connect to the Internet, the first time it just dies unexpectedly. It offers me the "Details" option, so I click this. Then it tells me I can't get the details, because I don't have the "Debug" option switched on. It asks if I wish to turn it on, so I say yes. Then I connect again, and it always works fine. I need to know how to switch the Debug option on automatically, but I don't know which dialog box (I'm guessing it's "Modem Commands") nor what to type in. Could someone help me here? The Mad Echidna 04:36, 23 August 2006 (UTC)

I think you should have a /etc/ppp/options file, which contains options for KPPP (and maybe also for similar programs). Putting "debug" without the quotes on a line by itself in this file should be what you want.-gadfium 06:03, 23 August 2006 (UTC)

Resolutions and video memory

Hi. Is there a general way to calculate how much video memory would be needed for a said resolution and bit depth? For instance, 1024x768 at 24 bits. My computer keeps saying I need over 5 megabytes to achieve that bit depth. How could I find out how much I have? This is a Debian GNU/Linux system, and the display card is Matrox Millennium or Millennium II. Thank you very much in advance. –Mysid^(t) 12:05, 23 August 2006 (UTC)

Well you have 1024×768=786432 pixels, and each of them requires 24 bits of memory, so in total you'll need 18874368 bits, which is the same as 18 MiB. At least that's what my naïve reasoning tells me. These days, however, graphics cards do more things than just store and output the current image – they do 3D rendering, for example – so you typically have a lot more memory than is needed to just display an image. —Bromskloss 13:11, 23 August 2006 (UTC)

That's 24 bits, 3 bytes. So that's only 2359296 bytes, a little over 2Mbytes. I think the card wants the same again for double buffering. So it's a bit more than 4Mbytes, hence the need for 5. You may be able to turn off double buffering to get it under 3. Middenface 13:14, 23 August 2006 (UTC)

Of course, you're right, I forgot to divide by 8. I felt 18 MiB was a bit much, but didn't think too much about it. —Bromskloss 13:37, 23 August 2006 (UTC)

Back in the "old days", a video card might provide as little as 4MB of video memory — and brag about it; these days a card selling for under US$ 100 may have 256MB onboard. For simplicity, assume four bytes per pixel; then multiply the resolution width times height times four to get the number of bytes to store a single screen. Let's consider a slightly more expensive card, the MSI NX6600-VTD256 using a GeForce chip from nVidia. It supports a maximum resolution of 2048×1536, which our formula says should require 12MB. But it also supports video in, MPEG decoding (programmable) for DVDs, animation (which may use triple buffering), pixel shaders, and especially 3D texture mapping, among other features. That's a sophisticated special-purpose computer on that card, and it needs memory to get its jobs done. Actually, these days the graphics processors are so fast and flexible that programmers are beginning to use them for tasks other than graphics. --KSmrq^T 14:44, 23 August 2006 (UTC)

Thanks for the suggestions, I'll try to switch off some extensions. (I know the card's a bit outdated, but I can't spend hundreds of euros in computer equipment, plus I'm not a gamer. :-) –Mysid^(t) 16:18, 23 August 2006 (UTC)

Cards do not typically support all resolutions even if they have the memory. To find out more about exactly what you have for a graphics card, you could try using a utility like SiSoftware Sandra Lite or Belarc Advisor. It will also be able to tell you what kind of graphics slot you have, which will limit your choices if you do decide to update your card. Find some spare change under the cushions and shop around; it's remarkable how much you can get for how little these days, because Moore's Law has been especially kind to graphics. --KSmrq^T 19:04, 23 August 2006 (UTC)

Well, thanks for the advice, but those programs seem to be made for Windows. I have a PCI slot, which limits my chances for new cards (also I'm poor). And before I bought the card I ensured that it supports resolutions up to 1176 (or something) pixels wide with 24 bits. But according to my friend's calculations ((3 * displayWidth * height * (pScrn->bitsPerPixel >> 3)) / 1024 = 6912), the resolution I wanted, 1024 x 768 x 24 bits, does not fit into 4 megabytes. So, case solved. –Mysid^(t) 05:37, 24 August 2006 (UTC)

(Wipes egg off face.) Forgive me, you did state "This is a Debian GNU/Linux system". Sorry for the unhelpful software links, and for lumping you with the Windows masses. A PCI slot seriously limits your upgrade options. But how can it be that you verified before purchase support for a higher resolution, but now think the card inadequate? Is it possible the higher resolution forced a reduced pixel depth, say 16 bits? Anyway, the precise model of your Matrox card should lead to a definitive answer. --KSmrq^T 12:12, 24 August 2006 (UTC)

lspci says "VGA compatible controller: Matrox Graphics, Inc. MGA 2064W [Millennium] (rev 01)". I bought it from a web auction, it was sold as "Millennium II". I searched the web for Millennium II and found a chart with the supported resolutions. Well, seems like I've been cheated, or maybe I just ignored the fact that he sold it as a 4 MB Millennium II, whereas the chart was for 8 MB. Thanks anyway, and sorry for the egg. Says the elitist Linux user :), –Mysid^(t) 21:26, 24 August 2006 (UTC)

CPU fan making lots of noise

I have a computer that has an Inpel Pentium 4 3 GHz processor, that while running it for a while the CPU fan starts to make a loud noise, that gets louder as the computer runs. It is a humming sound, and it can get annoying. I know that this is a heat-related issue, but would like some help as to how to keep this from happening. --Willy No1lakersfan (Talk - Contribs) 15:05, 23 August 2006 (UTC)

If it gets louder as the computer runs, then it's probably something expanding as the system heats up. How long has it been doing this? As long as you've had it? Just in the summer? Are you sure it's the fan and not the hard drive? Some computers are built with fans that are not powerful enough to properly cool the computer, and fans get dirty too. I live somewhere very dusty, and I've burnt out a fan. Apparently it was too weak for my system, but I also let it get really dirty. Now I have my fan cleaned out every year at least. OR, it could be something simple like the fan screws have gotten loose and it's vibrating against the tower walls. So that's what I'd check first. Actually, just take the covers off your tower and run the computer without them, and see if it still happens. If it doesn't, it might be that the unit is cooler without the case, or it might be that there's nothing to vibrate against. Then check the screws to make sure it's installed solidly. Then try putting the case back on. Anchoress 15:14, 23 August 2006 (UTC)

Thanks for the suggestions. The computer has had lots of dust in it, and I have tried to clean the dust out but the noise will come back about a week after I clean it out. This has only happened about 6 months after I first used the computer. I will try to dust it out again, and checking what you have suggested. --Willy No1lakersfan (Talk - Contribs) 15:43, 23 August 2006 (UTC)

That's cool. You need to know though, that it's waaaaayyy better to take your computer in and get it cleaned. In fact, lots of people recommend against trying to clean it yourself, because you can inadvertently push dirt deeper into the system. It's not expensive, and it's quick, to have a technician do it. Anchoress 16:01, 23 August 2006 (UTC)

It's also possible that the fan's bearings are worn, which can only be fixed by replacing it. --cesarb 16:21, 23 August 2006 (UTC)

I went looking into the case, and I found that the only fans that I have is the CPU fan and the fans for the power supply. Could it be a possibility that since the humming sound only occurs when the system has been running for a while and gets warm inside, that I need to add a case fan? I am thinking that a case fan added to the back of the case will pull the warm air off the CPU and out of the case. Let me know if this theory would work. --Willy No1lakersfan (Talk - Contribs) 18:16, 23 August 2006 (UTC)

3D/4D Graphing software

I know that there are many different 2D graphing softwares which can graph formulae and equations relating to x and y. My question is: Are there equivalent softwares which can graph formulae or equations which have three variables as 3D graphs, or even those with four variables as a 4D graph (presumably by showing a 3D graph change over a few seconds, using time as the forth dimension?

Thanks. —Daniel (‽) 22:01, 23 August 2006 (UTC)

I believe this question was asked here recently: [[1]] StuRat 23:27, 23 August 2006 (UTC)

Thanks. —Daniel (‽) 11:42, 24 August 2006 (UTC)

Konqueror krash?

This link was originally in WP:RD/S, and the popup that opens seems to crash Konqueror:

[2]

Any ideas? --M1ss1ontomars2k4 ^{(T | C | @)} 23:11, 23 August 2006 (UTC)

It doesn't crash my Konqueror, the pop-up opens perfectly normally. Then again, I'm using Konqueror version 3.4.2 without a Flash plugin in it, which might explain my immunity. -- Daverocks (talk) 07:13, 25 August 2006 (UTC)

Normally I wouldn't bring up this crash here because I am using KDE for Mac OS X, but unfortunately it's some old version (3.2, actually) and the KDE is really buggy anyway. But some other guy on WP:RD/S got the same result, so it's duplicatable O_o. --M1ss1ontomars2k4 ^{(T | C | @)} 18:59, 26 August 2006 (UTC)