Wikipedia:Reference desk/Archives/Computing/2006 September 4

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September 4

MEPIS deleted my files!

I recently used a simply mepis live cd to cut and paste files from my laptop hard drive to a usb hard drive. I finished transfering the files, but i can't see any of them. All of the folders are intact, however the files are not there. An interesting point is that whenever i check the root of the folder i copied my files too, it reads that it contains 12gb of files(the amount I transfered) leading me to believe that they are not completely deleted. Any help would be appreciated, the sooner the better. - Ridge Racer 02:48, 4 September 2006 (UTC)

Sounds strange. If you use the command line to list the files at the destination, do you see them? Dysprosia 03:04, 4 September 2006 (UTC)

I havent tried that, could you give me an example of the command to run in console, today is the first day in my life that ive ever ran linux for more that an hour at a time. - Ridge Racer 03:06, 4 September 2006 (UTC)

I don't know where your USB drive is mounted, so I can't be entirely specific. The ls command lists files. If you can get a command line with the current directory at your USB drive, then you can try that. Dysprosia 03:31, 4 September 2006 (UTC)

I actually attempted to find out on google. My drive is at mnt/sda1 so i used ls and tried to display the contents of the root folder where i transfered my files. I found three containing folders, but no files. Also, for additional information, my usb hard drive and laptop hard drive are both fat32. Should I consider a file recovery utility? - Ridge Racer 03:35, 4 September 2006 (UTC)

Did you properly unmount the usb drive before removing it? That could be your problem. Try fsck/chkdsk to see if it recovers the files. --Russoc4 14:30, 4 September 2006 (UTC)

Now That you mention it, I believe that I removed the drive without unmounting it. I mean it wasn't being cached, but I still didn't unmount it. I'll give both of those a try. - Ridge Racer 17:27, 4 September 2006 (UTC)

I think you are wrong in saying it wasn't being cached; AFAIK, Linux quite agressively caches the content of mounted disks, and the only way to make sure everything has been written to the media is to sync it or umount the media. --cesarb 17:32, 7 September 2006 (UTC)

importence of computer

sir pls I want to know about importence of computer in chemistry

No, this couldn't be a homework question could it? — [Mac Davis] (talk) (Desk|Help me improve)

• Just have a look around a chemlab and tell me how things like electron microscopes, mass spectrometers and such would work without computers... - Mgm|^(talk) 10:13, 4 September 2006 (UTC)

Or, if you're in a high school, probes, your calculator, and the textbooks are you are reading out of would not be there without computers. — [Mac Davis] (talk) (Desk|Help me improve)

See Computational chemistry. ~ Porphyric Hemophiliac § 02:08, 11 September 2006 (UTC)

Windows 98 login problems

To start with: This system is totally unsuitable for anything higher than Windows 98. Botting the system takes too long already, so I prefer suggestions on how to solve the issue rather than run away from it. Someone altered my sister's computer in such a way that she has to select a user profile before she logs in (which she finds annoying because it requires her to hit return half-way through a 5-minute startup procedure). When I go into the control panel to alter this I get a error message that says I can't delete the profile for the user that is currently using the system. How can you shut this crap off altogether so you're left without any profiles, but simply a straight login? - Mgm|^(talk) 10:23, 4 September 2006 (UTC)

I think that if you go to the network part of the control panel and delete the netbios/netbeui and/or windows-file-sharing (SMB) elements then this goes away. That's assuming you don't need windows file and printer sharing (i.e. that it's a free-standing machine); the reason it's asking who you are is that its anticipating being asked for authentication-info by network resources like file shares and printers that you might be trying to connect to later. If all you do is TCP/IP networking (web, email) then you don't need to be providing that authentication info, and deleting the SMB stuff should obviate the need for (and thus eliminate) the dialog. -- Finlay McWalter | Talk 10:34, 4 September 2006 (UTC)

Hibernate mode in Computers - Disadvantages

I would like to know what are the disadvantages of keeping the laptop in Hibernate mode all the time.Can I do it regularly with my Laptop without shutting it off for a faster 'Start up'?

Some versions of Windows (particularly pre-XP, but this holds true for XP as well) benefit from being properly rebooted once in a while - it clears the memory and allows the OS to do some housekeeping. How often you 'need' to reboot depends on how and how much you use your PC, as a rough estimate, for average use, once every few days should be sufficient. I'm going to assume that you're running Windows, MacOS and Linux don't need to be rebooted anywhere near as often and can run for weeks without too much trouble.

Other than that there aren't really any disadvantages to hibernation - it works quite nicely, and speeds up your startup times immensely! :) — QuantumEleven 13:18, 4 September 2006 (UTC)

One disadvantage is that it stores the internal state of all running programs on the disk. So if you had a secure program open (like an encryption program or a key storage locker) then potentially the passwords or encryption keys. Such programs are generally quite assiduous about keeping such information in special non-swappable allocations, but most OSes don't supply a special "don't swap, don't hibernate" kind of allocation, and don't supply applications with the "we just got unhibernated" message they'd need to make sensible use of that. So if you had an encryption application open and you hibernated the machine, the raw keys would likely be right there in HYBERFIL.SYS, and if your laptop was stolen at that point, someone could read that data right out. -- Finlay McWalter | Talk 16:45, 4 September 2006 (UTC)

note: the filename is hiberfil.sys not hyberfil.sys. 68.32.91.159 22:35, 4 September 2006 (UTC)

Another disadvantage is that some laptops still use some battery power while in Hibernation mode, so if it's in Hiber mode for too long your battery will die. ~ Porphyric Hemophiliac § 02:10, 11 September 2006 (UTC)

What is computer education?

What is computer education? How is it defined?

In what context? Homework questions are not allowed here, but I think you might be refering to basic computer literacy. Or possibly even computer-based training. --Russoc4 14:34, 4 September 2006 (UTC)

Computer Education: Education regarding computers. :) ~ Porphyric Hemophiliac § 02:11, 11 September 2006 (UTC)

Screen resolution changed from 1024x768 to 768x1024 - how do I undo?

A couple of weeks ago, while using my computer, the screen suddenly rotated 90-degrees clockwise. Checking the Control Panel Display properties reveals my screen resolution has somehow changed from 1024x768 to 768x1024.

I restarted the computer, and before Windows loaded, the screen appeared correctly. However, once Windows loaded, the screen was in the wrong position (768x1024) again. According to the Device Manager, my monitor is working properly. Therefore, I think this is a problem with Windows' configuration, and not with my monitor.

How do I change the resolution back? My system specification: Windows XP, Home Edition, Serivce Pack 2, 3.0GHz Intel Pentium 4, 512 MB RAM. I consider myself moderately computer literate.

--J.L.W.S. The Special One 14:54, 4 September 2006 (UTC)

Try pressing CTRL+ALT+Up arrow. This should rotate it back in place.

Failing that, look at the settings for your graphics card to determine the proper hotkey. You can also turn this feature off from there. --Pidgeot (t) (c) (e) 15:23, 4 September 2006 (UTC)

It works! Thanks very much! Where can I get more information about this? --J.L.W.S. The Special One 03:34, 5 September 2006 (UTC)

Control Panel > Display. --Proficient 17:58, 4 September 2006 (UTC)

Dual Monitors of Differing Sizes: Linux

I've got a 20-inch LCD monitor running at 1600 x 1200, and a 15-inch LCD monitor runing at 1024 x 768. My graphics card is an nVidia GeForce 6600 GT. I'd like to have both monitors running at their aforementioned resolutions in a dual-head setup. I've searched and found several solutions, all of which either want monitors with identical resolutions (TwinView), or which work, but reduce my 1600 x 1200 monitor to 1024 x 768 (Xinerama). Does anyone have any experience/suggestions? -- Braveorca 17:14, 4 September 2006 (UTC)

Are you running X.org? If you are, you can try manually editing xorg.conf. Type "man xorg.conf" (without the quotation marks) into your terminal for instructions on how to do this; the section that deals with multi-head setups is "Serverlayout", but you might need to edit others. If you're using XFree86, the equivalent file is XF86Config. I haven't tried this because my computer only has one monitor, but the ServerLayout section can have multiple screens, which can have their own "Display" subsections, which can specify different video modes. (By the way, it might be a good idea to back up the configuration file before you edit it.) Hope this helps! --Cadaeib (talk) 18:57, 4 September 2006 (UTC)

Posted here is the xorg.conf I came up with - it sitll doesn't work. Are there any obvious mistakes? I've tried to force the modelines into the resolutions I want, and yet it does not seem to be working. Any help's appreciated. --Braveorca 20:53, 4 September 2006 (UTC)

If you want a working dual-monitor configuration for reference (I run 1800x1350 and 1024x768), here's the relevant section of my xorg.conf:

Section "Device"
   Identifier  "nvidia0"
   Driver      "nvidia"
   BusID       "PCI:1:0:0"
   Screen     0 
EndSection

Section "Device"
   Identifier  "nvidia1"
   Driver      "nvidia"
   BusID       "PCI:1:0:0"
   Screen      1
EndSection

Section "Screen"
   Identifier  "Screen 1"
   Device      "nvidia1"
   Monitor     "Sony Triniton"
   DefaultDepth 24

   Subsection "Display"
       Depth       24
       Modes       "1024x768"
       ViewPort    0 0
   EndSubsection
EndSection

Section "Screen"
   Identifier  "Screen 2"
   Device      "nvidia0"
   Monitor     "Samsung 997MB"
   DefaultDepth 24
   Subsection "Display"
       Depth           24
       Modes           "1800x1350_68.00"
       ViewPort        0 0
   EndSubsection
EndSection

Section "ServerLayout"
   Identifier  "Simple Layout"

   Screen 0 "Screen 2"
   Screen 1 "Screen 1" rightOf "Screen 2"

   InputDevice "Mouse1" "CorePointer"
   InputDevice "Keyboard1" "CoreKeyboard"
EndSection

The only potentially-significant differences I see are that the ServerLayout line identifying the first screen in yours has a "0 0" that I don't, and mine has "ViewPort" entries for both screens that yours doesn't.

When you say your system "doesn't work", what exactly isn't working? --Serie 23:06, 6 September 2006 (UTC)

RAIDing hd's w/ different rpms

looking to raid a 74gig (ATA150) raptor w/ a 250gig (SATA2) western digital. i've never raided a hd before, and was wondering if there are any weird compatibility issues.

WindowsXP (32) Asus A8N-32 SLI Deluxe mobo HD's ...see above

thx

One is 10000 RPM and the other is 7200 RPM, correct? I don't think it is possible because it is highly recommended that you do RAID with the same kind of hard drives. Plus it will only raid taking the lowest of the two as both -- both HDDs will only manage 74 GBs. --Proficient 18:00, 4 September 2006 (UTC)

Setting processor affinity

I use VLC media player, which seems to be the de facto choice of media player here. However, I run into stability issues when I enable hyper-threading. Assigning VLC to processor #1 fixes this, so I was wondering about an automated way to do this?--Frenchman113 on wheels! 20:07, 4 September 2006 (UTC)

ya thats right; do you know a good source to check out questions like this? (The preceding comment not affiliated with Frenchman113).

Oww, my eyes

I just installed kubuntu 6.06 on my celeron 1.7ghz computer (specs at user:crazytales56297/B0x3n) and it defaulted to 60Hz screen refresh rate. I want to change it to 75Hz, as my monitor is capable of it. (it's a compaq 1024 14") But when I go to K menu -> System settings -> Display, it won't let me change to 75hz, the only option is 60hz. This is pissing me off as I already have bad eyes, and i don't need to make them any worse by using a 60hz screen. Also, it detected my graphics hardware as i810, but it's i845. Is this a problem? Many thanks, »ctails!« =hello?= 22:48, 4 September 2006 (UTC) PS: can you tell i'm a linux noob? :P

Most likely it only supports the higher refresh rate at lower resolutions. Try lowering the resolution then increasing the refresh rate. Also, the darker the screen, the less annoying a slow refresh rate becomes, so turn the lights off in the room and/or draw the shades, turn the brightness down on the monitor, and, wherever possible, change the background color to a nice dark color. StuRat 04:46, 5 September 2006 (UTC)

I solved the refresh rate problem by upgrading to a different monitor. But is it okay that it detected my graphics hardware as i810 when it's actually i845? »ctails!« =hello?= 15:23, 5 September 2006 (UTC)

If the screen looks OK, then it is OK. StuRat 04:59, 7 September 2006 (UTC)

hi a related question that probably wont be answered since it is so far up the page but, if i hav ea monitor with a 60 hz recommended setting (its the del 19 inch that came with the e510's if you know naythign about it) but i change my windows settings to 75 hz, will i see screen refresh rate improvement? Modesty84 18:06, 7 September 2006 (UTC)

I'd say one of these will happen:

• It will accept the 75 Hz and look better.

• It will stay at 60 Hz even when you change the setting to 75 Hz.

• The screen will be messed up, showing static or maybe reduced resolution.

The only way to find out for sure is to try it. StuRat 05:30, 10 September 2006 (UTC)