Wikipedia:Reference desk/Archives/Computing/2010 February 3

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February 3

Tux Picture Vs Windows Logo

I was once saw this image of a computer generated Tux holding a gun up to the Windows logo. Does anybody know where on the internet I can find it? --Melab±1 ☎ 02:33, 3 February 2010 (UTC)

Like this? Strangely, I found many (MANY) pics of Tux pissing on the Windows logo. -- kainaw™ 05:50, 3 February 2010 (UTC)

No it had a Windows Vista logo with hands and legs, hands up in the air with a pistol (not pissing) being pointed at it by Tux. -Melab±1 ☎ 22:32, 6 February 2010 (UTC)

http://images.google.com/images?q=linux%20vista
http://www.crystalxp.net/galerie/img/img-wallpapers-linux-vs-vista-rastakouere-11774.jpg
¦ Reisio (talk) 06:05, 8 February 2010 (UTC)

Automatic Logoff at Login in Vista

On one of my administrative accounts, every time I log in the account, I get immediately logged off. A temporary workaround was to log in in safe mode and create another administrative account (because I can't use the web and anti-virus in safe mode). So I scanned the other user account and there are no viruses, this seems to be a configuration error. This problem started right after I installed php environment and restarted the computer. I have a vista64 os, anyone here know what could be causing this.

72.188.46.220 (talk) 02:51, 3 February 2010 (UTC)PHPNoob

In my experience (twice now, unfortunately) that would be one of the signature "features" of Vundo. Try another virus scanner, and soon. DaHorsesMouth (talk) 04:26, 3 February 2010 (UTC)

It is not a virus, I scanned the hard drive already. Anyone know how to find the start up scripts for the broken account from the working account?

72.188.44.11 (talk) 13:20, 3 February 2010 (UTC)PHPNoob

How about uninstalling the PHP tools? It seems pretty bizarre that any software, in the course of normal operation, would force an auto log-off of the admin user. Checking the event viewer for any additional clues is a good place to start. Also, check the startup folder of the affected user. Finally, it might be worth checking the computer with a virus scanning boot CD, such as the one available from BitDefender, since this will even detect viruses that have protection mechanisms. --Jmeden2000 (talk) 14:00, 3 February 2010 (UTC)

"Also, check the startup folder of the affected user" - I can't seem to find this folder. Also mscofig does not show the other account's start up configuration.

72.188.44.11 (talk) 14:23, 3 February 2010 (UTC)PHPNoob

In the user folder, look in the start menu for the Startup folder. The PHP tool kit may have stuck something in there that is causing an unintended error and leading to the log off. --Jmeden2000 (talk) 15:30, 3 February 2010 (UTC)

And some viruses interfere with known virus scanners, so use more than one virus scanner. Comet Tuttle (talk) 15:38, 3 February 2010 (UTC)

If you have a spare blank CD-R, make an ISO image of the BitDefender rescue disk, it is an absolute wonder. It boots a completely separate OS (linux), applies current virus definitions, and scans any attached drive. Many viruses can hide from or otherwise inhibit the operation of any virus scanner out there, if given the chance. Running the scan off-line is the only way to be sure. --Jmeden2000 (talk) 17:56, 3 February 2010 (UTC)

How to use HD video in flash, or put flash animation over HD

(I've moved this question from the Miscellanous desk. There were no answers there yet. --Anonymous, 06:50 UTC, February 3, 2010.)

I use flash and have begun shooting HD video, using primarily imovie to edit. How do I use my flash animation IN or OVER my video without importing it to flash and totally losing the quality? —Preceding unsigned comment added by 66.175.86.29 (talk) 05:25, 3 February 2010 (UTC)

For IN: Export the Flash to something that you can import into iMovie, e.g. MOV. There is an option to do this under the File menu, I believe. For OVER: Hmm, much trickier, I assume you mean as some sort of transparent overlay. I'm not sure you can do that with iMovie unless you import the iMovie segment into Flash (you can adjust the quality settings when you do so, of course), and then re-export the whole thing as MOV. You will lose some quality in the transcoding, though. --Mr.98 (talk) 13:33, 3 February 2010 (UTC)

Choosing a "Favorites" Link Opens a New Window

Morning,

I know there's likely an easy fix to this, but I looked for it and couldn't find it. I didn't want to bother our IT guys if I didn't have to.

I am running IE7 on Vista, on a Dell 630. Whenever I choose anything from the "Favorites" menu, rather than just going to that website, the browser opens the favorite in a new window. I have tried unchecking the "Reuse windows for launching shortcuts (when tabbed browsing is off)" checkbox in the advanced tab of the properties, but that's not what I need. Anyway. Thanks for your help. Sorry if this was resolved elsewhere. Kingsfold (talk) 15:08, 3 February 2010 (UTC)

IE does this for me if my Shift key is held down while I click the Favorite. Hammer on your Shift keys a few times to make sure they are not stuck? Comet Tuttle (talk) 15:37, 3 February 2010 (UTC)

Good thought (I thought the same thing), but I'm typing just fine.... Kingsfold (talk) 16:07, 3 February 2010 (UTC)

Quad core Q

I replaced my really slow 500 MHz computer with a much faster 2800 MHz quad core, but it doesn't seem any faster. I'm running Windows XP SP3. Is it possible it's only using one of the 4 cores ? If so, is there any way to get it to use them all under XP, or do I need to go to another O/S ? StuRat (talk) 16:03, 3 February 2010 (UTC)

As you probably know, the major performance issue of a computer is the HDD. When you load a program, for instance, the CPU is probably just waiting for the HDD to give it some data to process. If you want to see the increase of performance, you need to do something CPU intensive, such as ray-tracing, or some other mathematical computation. --Andreas Rejbrand (talk) 16:18, 3 February 2010 (UTC)

And: a quad-core CPU @ 2.8 GHz is not equivalent to a single-core CPU of 11.2 GHz. A single thread (such as simple-threaded process) will only be able to utilize one of the cores. The true benefit of a multi-core CPU is that you can do may things at the same time, such as one ray-tracing operation, one TV recording, one download, one music streaming process, and one prime factorisation, at the same time that you run an intensive 3D game. But some programs (not too many though), such as Blender, will automaticaly create many threads to really use all four cores, which should be rather close to (but not quite) an effective 11.2 GHz core, I guess. --Andreas Rejbrand (talk) 16:22, 3 February 2010 (UTC)

I didn't think it had four 2.8Ghz cores, I thought it had four 0.7GHz cores. StuRat (talk) 19:23, 3 February 2010 (UTC)

Sun microsystems used to measure GHz like that on their sparc machines - but for a AMD or Intel processor 2.8 GHz quad core means 2.8 each, not total.87.102.67.84 (talk) 13:17, 4 February 2010 (UTC)

Additionally, putting more RAM in a machine will often give more of a performance boost than a new CPU or hard drive ever will. Since you're using Windows XP, chances are that 4GB of RAM is the maximum the OS can use. I recently "fixed" a computer that was having problems by upgrading the RAM from 512MB to 2GB. This was more than enough to avoid swapping out to virtual memory during normal daily tasks which in my own experience is one of the biggest causes of people complaining about slow computers. Caltsar (talk) 16:37, 3 February 2010 (UTC)

Quibble: The 4GB number is a theoretical maximum on 32-bit XP, but the actual maximum is always less. A 32-bit XP machine with 4GB of RAM installed will show less than 4GB, depending on the I/O devices. Here is a good discussion of same. My 4GB XP machine, which has a 512MB video card, correspondingly only shows 3582MB of physical RAM available. Comet Tuttle (talk) 17:32, 3 February 2010 (UTC)

Very true, I left that out to avoid complicating things further as 4GB of RAM (as in physical sticks of the stuff) is the maximum a 32-bit OS can address before taking into account other overhead in addressing space. And to add to my previous comment before anyone points this out, I was referring to RAM speeding up a system most significantly in the way a user perceives the speed and not the actual benchmarks. RAM tends to be the bottleneck in this sort of scenerio. Of course, if StuRat (edited, put the wrong name here!) already has plenty of RAM, the Hard drive or general OS bloat could also be culprits. Caltsar (talk) 17:51, 3 February 2010 (UTC)

I agree with the remarks above (and my 64-bit Windows 7 machine has 6 GB of RAM). --Andreas Rejbrand (talk) 17:56, 3 February 2010 (UTC)

It's not the OS; it's the applications you run. To view your four cores' workload, hit ctrl-alt-del to bring up the Windows Task Manager, and then click the "Performance" tab to look at the pretty graphs. Depending on what applications you use, it's likely that only one core will be highly tasked, but, as Andreas Rejbrand notes, some applications do use them all — when Adobe Premiere renders video, for example. Comet Tuttle (talk) 17:23, 3 February 2010 (UTC)

Oh, since this is of interest to you: In the Task manager, click the "Processes" tab and then you can right-click on any process and choose "Set Affinity" to force a given process to run its threads on particular cores. You shouldn't ever feel that this is necessary to optimize your system, but it's an interesting toy. (I have been told that using this technique to restrict Microsoft Outlook 2007 to a single core does stop Outlook from locking up your machine periodically.) Comet Tuttle (talk) 17:26, 3 February 2010 (UTC)

XP can utilise all the cores (with the disclaimer above that a single threaded application may be bound to one core) - but what is not faster? You can speed up start up times by adding the program to the startup folder at the expense of memory. Otherwise - the hardisk may slow you down, or possibly graphics is now your bottleneck.87.102.67.84 (talk) 19:22, 3 February 2010 (UTC)

That sounds like exactly what I want, but I suspect it only works for the current session. Is there any way to have Explorer always use a specific core and have my PowerDVD use another, etc. ? Then maybe the DVD I'm playing wouldn't hiccup when Windows decides to go check for updates or something. StuRat (talk) 19:23, 3 February 2010 (UTC)

The relevant command seems to be 'start' eg at the command prompt something like "start /affinity 4 C:/powerdvd.exe" to start powerdvd on processor 4 (you can put the command line arguments in a shortcut or batch file for ease of use), priority is also set using start. I'm not sure if using affinity prevents other processes from using a core, setting priority higher might also work for your needs.87.102.67.84 (talk) 19:43, 3 February 2010 (UTC)

I'd like to try that. What's the syntax for setting a higher priority ? StuRat (talk) 20:09, 3 February 2010 (UTC)

In task manager you can right click on a process and reset the priority - I believe this is temporary, to set priority using start it's

[1]> start /<priority> <application>, e.g. start /high winword.exe
To do the same thing from a shortcut just use: cmd /c start /<priority> <application> copied from link and modified

Note <priority> uses words (possibly you can use numbers too), in cmd.exe type "start /?" for a list of commands and accepted words - I believe that using 'realtime' priority can be problematic. So you'd type something like start /high dvdplayer.exe (or whatever the exe file is called - full path also needed I think). I've no experience of using this myself, but the info is so often repeated I assume it is accurate.

That said I echo what is said below - on XP with a many times less speedy processor I don't experience such problems - though I don't really multitask more than 2 or 3 things at once in general...87.102.67.84 (talk) 21:56, 3 February 2010 (UTC)

Oh almost forgot, many programs let you choose their priority - from memory: SMplayer VLC player (also FFmpeg) either via the command line or deep within the settings.. One issue is that changing the priority for 'dvdplayer' using start might not affect the settings of programs that it itself initiates (anyone got the answer to this)? I think it's likely that your personal dvd player also will have such a setting (probably well hidden) - in the programs folders try looking at installation notes, or other readmes - I'd bet there's a way for your program too (without messing with the start command)87.102.67.84 (talk) 22:30, 3 February 2010 (UTC)

That should definitely not happen. I usually record TV and perform a very, very lengthy mathematical simulation while playing GTA: San Andreas (and maybe a download too). --Andreas Rejbrand (talk) 19:43, 3 February 2010 (UTC)

Well, this is not a relevant remark, but I think that you would love Windows 7. In addition, I believe that Windows 7 works rather well with solid state disks, which are faster than conventional HDDs. It might be a good idea to put the OS and most programs on a SSD, but I have never tried that. Actually, I am very happy with the performance of my computer, even though it has a conventional HDD. This might be because I have a very high-end CPU, a lot of RAM, and - most importantly - never shut down the computer. In Windows 7, the "hybrid" stand-by mode is great. The computer is completely silent in this mode, and you can wake it within a couple of seconds. In addition, if you would loose the power during stand-by, you can still resume your work, for the most important parts of the RAM have been saved to the HDD. It will take some time to resume, but no data will be lost. --Andreas Rejbrand (talk) 19:54, 3 February 2010 (UTC)

You never shut it down ? Does that mean Windows 7 has completely eliminated the memory leaks which made periodic reboots necessary ? StuRat (talk) 04:46, 4 February 2010 (UTC)

I never shut down my Windows Vista PC either. But due to automatic updates requiring system reboots, I did never obtain an uptime of more than a couple of weeks, so I cannot say anything about the system stability for periods longer than that. --Andreas Rejbrand (talk) 09:54, 4 February 2010 (UTC)

In general, that's not necessary: the OS will automatically distribute processes to different cores when those cores would otherwise be idle (or under-subscribed). You need to use "Set Affinity" only when you want to use some other policy, like "these two long-running processes must share a core because I don't care how long they take and I'd rather have the other cores free for other usage as it arises". --Tardis (talk) 19:59, 3 February 2010 (UTC)

Thanks for the answers, so far. More RAM might be a good thing to try. I'd also like to try setting priority. Perhaps it might make more sense to lower the priority on all the other processes that are always running. Are there any common intrusive processes which could stand to have a lower priority ? How about Explorer.exe ? StuRat (talk) 04:55, 4 February 2010 (UTC)

I would not recommend chaning priorities; everything should work just fine when Windows schedules processes automatically. And I do not think that altering the priority of the Windows shell is a good idea... But I guess it safe to try; if something does not work out well, a reboot would fix the problem. --Andreas Rejbrand (talk) 09:52, 4 February 2010 (UTC)

Common sense tells me not to lower priority on explorer (no explanation given) - how ever you could lower priority on stuff like windowsupdate, googleupdate, adobeupdate etc - stuff that can wait. (not sure what they are called internally)87.102.67.84 (talk) 13:01, 4 February 2010 (UTC)

Before spending your hard earned cash on new memory I think Windows Task Manager can help you again. In the performance tab (where the CPU charts are), look at the bottom where it says "Commit Charge" (there's an article on that) - specifically look at the peak value, and compare it to total physical memory also found in "physical memory" (note "total physical memory" should be close to the amount of RAM you have) - if "peak value" of commit charge exceeds "total physical memory" then the computer will have had to use the hard disk to swap blocks of data in and out of ram - slowing it down. If the peak value is less then this hasn't happened (and you don't need more memory).

Note - look at the peak value after running windows for some time as you usually do, including all the stuff that you might do during the day. (The initial value at start up will be low).

You can monitor the effects on "total commit charge" as you open new programs. - it's always possible to max it out if you open enough browser windows etc - so just try normal activity.87.102.67.84 (talk) 12:58, 4 February 2010 (UTC)

(I'm 99% this analysis is correct - but please jump in if I've missed something obvious else. or maybe you meant to increase the number of utilised memory channels - not total ram?) 87.102.67.84 (talk) 12:58, 4 February 2010 (UTC)

interested in computers

If I wanted to learn more about computers, find out how they work, write my own programs, that sort of thing, where should I start first? And supposing I studied for an hour every day, about how long might it take to learn that sort of stuff? Would it be possible to do it all from here, just using my own computer and the internet?

148.197.114.158 (talk) 17:47, 3 February 2010 (UTC)

Definitely. There are tons and tons of self-taught programmers who are masters in their field. Take a look at Microsoft Small Basic for starters? Comet Tuttle (talk) 17:55, 3 February 2010 (UTC)

I am a self-tought programmer, and today I consider myself very experienced in Delphi and Win32 development. I learned programming at the age of 12 by studying sample code. At that time, there was a free Personal edition of Borland Delphi, but unfortunately, there is no such version anymore. But I believe that Microsoft Visual C++/C#/... Express Edition is free, isn't it? --Andreas Rejbrand (talk) 18:00, 3 February 2010 (UTC)

Yes, Visual Studio Express is free, link is here. Small Basic is free at this Microsoft link. Comet Tuttle (talk) 18:13, 3 February 2010 (UTC)

(edit conflict)Well Wikipedia's Personal computer article has some basic stuff about computer hardware, and you can click on each of the components to get more information on each bit (see the hardware section). Once you know a particular bit of hardware exists, you can search Google for it and likely get more good information. As for learning to program things, there are lots of good internet sites for learning that sort of thing. First you need to choose a language, I'd suggest Python, it seems useful and relatively simple. There are a list of tutorials for it here.

As far as how long it'd take, I think that'd depend on how much you wanted to know, I doubt you could ever know everything about everything computer related. It's more like a journey than a destination, you're not going to wake up one day and say "oh I know computers now". But you can probably learn the basics pretty quick and get a pretty good handle on Python within a week or two of daily use. TastyCakes (talk) 18:01, 3 February 2010 (UTC)

Python isn't unique in that sense. Most programming languages have highly similar concepts behind the structure. Once you understand the concepts, most of programming in a new language is just looking up syntax requirements. You know what you want to do (ie: use a for loop), but you just need to see what the syntax looks like. There are some languages which do not have the same general concepts as the majority of mainstream languages. You can safely ignore those and still be what most people would call a "computer expert." -- kainaw™ 22:28, 3 February 2010 (UTC)

True, Python uses very ordinary programming conventions, similar to C++ or Java or dozens of others. Its advantage, in my opinion, is a much more "beginner friendly" syntax and its large standard library to do all sorts of things very easily. I think Python is a good language to learn on for those reasons: you can learn the high level concepts of programming without (as many) semantic problems frustrating and slowing you down. TastyCakes (talk) 16:14, 4 February 2010 (UTC)

New question, I was looking around on the internet for a while and found this, http://en.wikibooks.org/wiki/C_Programming/A_taste_of_C , thought I might give it a go. It was going well right up until the running of the example program, which my computer insists does not exist, even though I can see it saved right there, where I put it. Nothing I've tried makes it see otherwise, so either I'm already doing something silly wrong, or this is a very long way of getting me to download a virus, which I hope it isn't. Any ideas? 148.197.114.158 (talk) 11:06, 4 February 2010 (UTC)

You should have two programs hello.c (the source file with the program text), and hello - the compile program you want to run.. Are you using windows - if so I wonder if you should compile to hello.exe - one possibility is that when you type "hello" (no quotes) into the command line windows might be thinking you mean hello is a command like "dir" or "cd".

ie try using "gcc -o hello.exe hello.c" (no quotes) - the .exe part signals to windows that the program is runnable.87.102.67.84 (talk) 12:46, 4 February 2010 (UTC)

Just tried that, doesn't work. It still insists hello.c doesn't exist. Perhaps if I renamed it something else... 148.197.114.158 (talk) 18:09, 4 February 2010 (UTC)

Yes try that - so you haven't even got past the compile stage (just to say - when you convert the text to a runnable program it's usually called "compiling")

If it doesn't work can you copy the error message (are you compiling at the command line - ie cmd.exe?) also have you got both the gcc program and the hello.c program in the same directory?87.102.67.84 (talk) 18:47, 4 February 2010 (UTC)

TEST - what happens if you type hello.c on it's own? Does the text editor open or not?87.102.67.84 (talk) 19:08, 4 February 2010 (UTC)

gcc might be a bit hard for beginners in windows - [2] - there are lots of others you can try - tiny c , and lcc are also c compilers - and the documentation seems easier to read, alternatively try an IDE there are lots to choose from.87.102.67.84 (talk) 20:06, 4 February 2010 (UTC)

OK, typing in the reccommended gcc -o hello hello.c brings up the messages: 'gcc: hello.c: No such file or directory' and 'gcc: no input files'. Typing just hello.c brings ' 'hello.c' is not recognised as an internal or external command, operable program or batch file.' I think I should just give up and try one of those others. 148.197.114.158 (talk) 20:16, 4 February 2010 (UTC)

• It may be just a matter of cd-ing or chdir-ing into the source directory (the directory where you saved hello.c) before trying to compile with gcc. From the error message, your gcc installation seems to be working fine, and you are running the gcc command from a directory other than the one where you saved the hello.c file. --Zvn (talk) 20:22, 4 February 2010 (UTC)

If typing hello.c doesn't work it's not there! it should open the file for editing with a text editor - type "dir" and tell us what you see - both gcc and hello.c need to be there. Are you familiar with using the command line - if not you probably need a quick lesson, (searcg for "cmd.exe tutorial" or read this http://www.bleepingcomputer.com/tutorials/tutorial76.html (only one page - scroll past the spyware adverts to the useful stuff below) or alternatively use a program with an included IDE.87.102.67.84 (talk) 20:55, 4 February 2010 (UTC)

Try This - use windows search to find 'gcc.exe' then open the folder containing this file. (there will probably quite a few things in it - don't be put off). The get your "hello.c" file and copy it to the same folder. Then using "run" in the start menu open the command prompt ("type cmd.exe") - now navigate to that folder in the command prompt, type "dir" to get a listing of the files - verify that both gcc.exe and hello.c are present. Then type the compile command.this should work. If you get stuck or get errors please ask.87.102.67.84 (talk) 23:51, 4 February 2010 (UTC)

Well, I'm getting there, it seems. It was trying to work from inside some other folder, so I've moved to the right place, both gcc and hello.c are next to each other in the same folder, the file opens when I type it to, but it still doesn't run. The file format is not recognised, and it returns 1, which does nothing. 148.197.114.158 (talk) 10:54, 5 February 2010 (UTC)

Good - 1 means an error (in C return 0 (zero) means ok ) - the compiler found the file but didn't like it. One possibility is that you've saved in the wrong format - compilers like simple text files (no fonts, bold, italic, or colours) - if you didn't before - use notepad to make the program - you can copy the old program into notepad and save the result - this also creates a simple text file. (Note the coloured program in the tutorial you are using is how it would appear in a special development program - but the actual file is just plain black on white text)

If you already had saved as a text file (not .rtf , .doc etc) the something else must be wrong. At this point I'd recommend trying another compiler to see if it's gcc or something else - tinyc is a small download from here http://bellard.org/tcc/ (see Downloads section a page or two down)- once the tcc-0.9.25-win32-bin folder has been extracted, open it, and the tcc folder as well - this is the place to put the "hello.c" file and the compiler is the program called "tcc" - to try compiling just type "tcc hello.c" - a file hello.exe should be made. If you get this far and tinyc/tcc works then the program at the least is generally acceptable, if it doesn't work in tinyc as well as gcc it need looking at.

I'm hoping that you've saved the file in the wrong format - as that is easier to fix.87.102.67.84 (talk) 14:51, 5 February 2010 (UTC)

You should consider trying a more simplisitic/easier language such as Microsoft Small Basic or Visual Basic.net to get started. Starting on C will be a bit of a headache...Smallman12q (talk) 16:14, 6 February 2010 (UTC)