Wikipedia:Reference desk/Archives/Computing/2008 May 20

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May 20

Help with files

HELP HELP HELP. I got a file from my friend but something is wrong with it! It is a folder. Inside the folder are 5 files. They all have the same name, but they're all different file types. There are:

• Song.1pk
• Song.pk
• Song.sfk
• Song.cue
• Song.wav

When I play that wav file in realplayer or windows media player, it is 45 minutes of static. What are the other files for??? How do I do this??? Thank you!--Goon Noot (talk) 01:12, 20 May 2008 (UTC)

The .pk file appears to be used by Adobe Audition ([1]) and the .sfk Sound Forge ([2]). The .cue file is likely to be a CD image of some sort which can be burnt onto a CD (or using specific software, its contents extracted) and the .wav file is predictable a WAVE file. Not sure what the .1pk file is for. If you can't play the .wav, I'm not sure what that's about because usually these sound issues are to do with lossy formats; there's hardly codec problems for .wav files out there... Perhaps the .cue file can be mounted using software like Daemon Tools and played as if it were an audio CD? x42bn6 Talk Mess 04:49, 20 May 2008 (UTC)

Does not sound good. Are you sure that your friend manually sent you the email? Could you check back on him/her in meatspace to confirm? Kushal (talk) 04:42, 20 May 2008 (UTC)

I changed the file type of the .wav to .dts and it plays on foobar now. What should I do with the other files?--Goon Noot (talk) 15:50, 20 May 2008 (UTC)

iPod storage

I am interested in buying a new iPod, but I'm not sure how may gb to get. When it lists that it can hold 8,000 songs, that's about 2 minutes each, but how many minutes of videos with sound does it hold? As I'll want songs, videos, and photos, what is the conversion rate of memory space taken up? Thanks, Reywas92^Talk 01:28, 20 May 2008 (UTC)

As a general rule of thumb, a non-audiophile listener will enjoy music that is about 1 megabyte per minute, and about half-to-a-third that for varying definitions of "audiophile" after that. Videos depend on a number of factors, but a random sample of videos I have seems to produce approximately 4 megabytes per minute of video. A picture at appropriate resolution for an iPod is probably going to clock in at 1/20th or 1/200th of a megabyte (my apologies, I'm a little too tired to trust my precision at the moment). A "decent" digital camera picture will probably clock in at, again, 1-2 megabytes (but that could easily be re-sampled to lower resolution; the iPod will have to dynamically, anyway). Keep in mind, you don't get the entire storage space for use - some gets used by the operating system. Still, 400 songs and 20 videos later, and I'm not even half full myself. Only so many November Rains out there, I suppose. -- Ironmandius (talk) 02:52, 20 May 2008 (UTC)

shaddy contractor

question removed by Zrs 12 (talk) 01:55, 20 May 2008 (UTC)

This question has been removed. As per Wikipedia reference desk guidelines, we are not permitted to answer any questions about legal advice. It is my suggestion that you ask a lawyer about the way in which to deal with anyone who has botched a job on your computer.

However, if you have any questions about how to repair your computer, we would be happy to try to help. Zrs 12 (talk) 01:55, 20 May 2008 (UTC)

How do I split the tabs?

Okay I am running an instant messenger on Windows XP 2002. When I open a lot of windows, some of them that are of the same type collapse into just one tab and it shows a number. How do I split it back into individual tabs?--Goon Noot (talk) 02:43, 20 May 2008 (UTC)

Right-click on taskbar. Click Properties. Deselect "Group similar taskbar buttons". -- Danh, 70.59.79.51 (talk) 03:27, 20 May 2008 (UTC)

What's wrong with my keyboard?

Pressing ~ causes a ¬ to appear. Pressing \ causes a # to appear. Pressing | causes a ~ to appear. Pressing @ causes a " to appear. Pressing " causes a @ to appear. Pressing # causes a £ to appear.

This problem occurs in some programs but not others and the programs it occurs in seems to keep changing! —Preceding unsigned comment added by 59.189.61.14 (talk) 11:50, 20 May 2008 (UTC)

Sounds like you have the British keyboard layout enabled. ----— Gadget850 (Ed) ^talk - 11:59, 20 May 2008 (UTC)

The exact same thing happends on my home pc, so I always get confused when I use someone elses that doesn't do it. For # you do "shift 3" on my keyboard. Bed-Head-HairUser:BedHeadHairGirl12:51, 20 May 2008 (UTC)

See Keyboard layout#QWERTY UK and Ireland. Assuming you have Windows XP, check your layout by following these instructions. ----— Gadget850 (Ed) ^talk - 13:10, 20 May 2008 (UTC)

CPU question

I saw a gaming PC with an advertised processor speed of 13 GHz. Is that actually possible? Or is that just the speed of all the cores added together? Could I actually achieve speeds of 13 Ghz, or would it only be that fast if I used all of the cores at once? Any explanation would be appreciated, thanks in advance! Scarian^{Call me Pat!} 12:47, 20 May 2008 (UTC)

Where is this PC ad? I'd like to see it. But 13GHz is misleading. I don't know of any consumer computers going above 5-6GHz even when cooled with liquid nitrogen. The chances are that they just added the speeds in the cores (8x 1.66 GHz or 4x 3.25+ cores). That being said, there are times where it will perform as well as a single core 13 GHz processor, particularly when video is involved. But of course, if you look at even the Sony PlayStation 3's massive amount of cores, getting games to use all that processing power is neigh on impossible. That, and you'd probably want graphics processing for video, unless some of the cores are made to be graphic processors. And I'll guarantee that none of the clocks in there run at 13 GHz, or anywhere near it. --Wirbelwindヴィルヴェルヴィント (talk) 13:31, 20 May 2008 (UTC)

I couldn't find the exact one I was looking at earlier, but here is a similar one: [3]. So its advertised speed at 9~ GHz is misleading? Silly me for being optimistic. You mentioned consumer PC's running at 5-6 GHz? Know where I could find any running at that speed? Scarian^{Call me Pat!} 14:45, 20 May 2008 (UTC)

Yea, that's a quad-core 2.4 GHz chip that they're advertising. You won't find any PCs running at 5-6 GHz without being able to get a supply of liquid nitrogen, as they're overclocked. And clock rates don't mean as much nowadays as they did back in the days, pre-3GHz. If the program (or game, probably, in this case) you're running can utilize more than one core well, a 1.66 dual core can perform better than 3GHz system. It gets harder to utilize the more cores you have though. --Wirbelwindヴィルヴェルヴィント (talk) 14:56, 20 May 2008 (UTC)

(after edit conflict)

Yep. The heating problems led Intel to go through the massive problem of dismantling in the consumer's mind, the idea of equating processor "power" with the clock speed. Just getting beyond 4 GHz was problematic and although I am sure Marketing protested wildly, Intel went ahead and began educating people that clock speed is not everything about a processor (a notion some say Intel itself put in the consumer's mind). As Wirbelwind, I would like to see the advertisement as well. Could you link us? Kushal (talk) 15:01, 20 May 2008 (UTC)

Was it Intel that reeducated people? I thought it was AMD, by making processors that outperformed Intel's at a lower clock rate. That kind of drove the point home. -- BenRG (talk) 16:11, 20 May 2008 (UTC)

That's what I thought too, cause IIRC, Intel was trying to push the frequency while others (like AMD and I think IBM) were saying they need to give up. --Wirbelwindヴィルヴェルヴィント (talk) 16:25, 20 May 2008 (UTC)

That's what's funny about it. Intel had to backpedal and side with AMD on the point. So, uh, both of them are trying to reeducate people now. 206.126.163.20 (talk) 21:41, 20 May 2008 (UTC)

PS: thanks for the link. According to AMD, it is a 2.4 GHz processor. The ebay seller is probably misleading you in the heading but in the specs, it says "2.4GHz (x4)". I am not sure if they want to be dishonest but they seem to give inaccurate information like calling their version of Windows "Genuine Windows Vista Premium 64Bit Included" where they probably skipped the word "home". I don't think I would buy a desktop in one piece until I did some basic research to figure out if it would be cheaper to build it myself or not. Kushal (talk) 15:01, 20 May 2008 (UTC)

Thanks for the replies guys! I'll try not to get duped! ;-) Scarian^{Call me Pat!} 15:36, 20 May 2008 (UTC)

Sounds obvious to me, but could it have been a misprint and actually 1.3GHz? Some (long?) time ago a 1.3GHz would have been a kick-ass gaming machine. Astronaut (talk) 18:08, 20 May 2008 (UTC)

free online soccer

my friend said it's possible to see live soccer matches on the internet for free. is it true --scoobydoo (talk) 15:34, 20 May 2008 (UTC)

It seems so from looking at this site, which lists software for streaming broadcasts. These are not soccer specific, or even sports specific. My suggestion would be to try some of those out (of course, watching out for adware and the like). Googled "live soccer match web." WDavis1911 (talk) 18:14, 20 May 2008 (UTC)

VoIP/IPKall: receiving incoming calls

I've been trying to get calls with an IPKall number, forwarding them to my FWD account; I'm using an X-Lite soft phone.

It doesn't work. I hear the ring tone of incoming calls, can intercept the call... and neither I nor the caller hear each other. I've read somewhere of other people having this or a similar problem, but didn't find a solution. I don't have any problems with a separate sipgate account which I've been using for months (using the sipgate X-Lite soft phone).

I don't mind changing VoIP company or soft phone--all I want is receiving calls from a "real" phone number, so that people without an SIP account can call me. Voicemail would be appreciated, but at this point I'd just like to get any calls. So any tips for what I should check or which other software I should use are highly welcome. Thanks a million! Thanks, thanks, Thanks for answering (talk) 15:36, 20 May 2008 (UTC)

C variable string

Is it possible to do a string like this ("%c%c",char1,char2) ? Something similar to the string generation in printf. I want to combine different elements of an array of characters into a string. Bastard Soap (talk) 20:57, 20 May 2008 (UTC)

sprintf works like printf, exept that the results goes into a character array. Sample code:

#include <stdio.h>

int main()
{
   char str[100];
   char o='O';
   char k='K';
   sprintf(str, "%c%c", o, k);
   puts(str);
   return 0;
}

Is this what you were looking for? Mind you, code using sprintf is very bug-prone, and also vulnerable to exploits, because of the danger that your program might try to put too large strings into the buffer. Using C++ and standard library strings is a better option. --NorwegianBlue ^talk 21:43, 20 May 2008 (UTC)

If you're adding individual chars you should be able to easily cook something up to count the number of chars you've added compared to the size of the string. sprintf'ing using string arguments (without buffer overflow protection), or doing chars and such without checks is a recipe for bad times, though. 206.126.163.20 (talk) 22:11, 20 May 2008 (UTC)

Thanks man, it was just the thing. Bastard Soap (talk) 22:38, 20 May 2008 (UTC)

AMD board

I have an old computer with an Intel motherboard and INtel chip. If i wanted to get an new AMD motherboard and remove the old Intel motherboard, would I need a different CPU case? In other words, would a case affect what i could put into a computer. --Randoman412 (talk) 21:41, 20 May 2008 (UTC)

As long as both motherboards conform to the same form factor, then there's no issue. And most normal-sized motherboards are ATX, so it will probably be fine. Different cases within the same form factor do have different amounts of air flow (and if you're moving to hotter components that might matter), different room for hard drives, and other differences, but the motherboard, CPU, powersupply, and normal sized expansion cards should all fit. 206.126.163.20 (talk) 21:43, 20 May 2008 (UTC)

And on a minor matter of terminology, just call it a 'computer case' or just a 'case'. A CPU is a pretty specific component inside the computer, and 'CPU case' sounds kind of like a CPU heatsink. 206.126.163.20 (talk) 21:56, 20 May 2008 (UTC)

Disk image/operating system compatibility

If I create a disk image on a USB flash drive with Disk Utility in Mac OSX, can I open that image on a computer running Mac OS9? Could I encrypt it? Are there any alternatives to disk images that can be used to secure/encrypt files that are compatible with both OSX and OS9? Thanks a bunch. Ilikefood (talk) 23:13, 20 May 2008 (UTC)

TrueCrypt has plenty of good reviews. Kushal (talk) 23:28, 20 May 2008 (UTC)

Thanks, but TrueCrypt needs 10.4 to run. Anything that will work with Mac OS 10.3.9? Ilikefood (talk) 23:49, 20 May 2008 (UTC)

Sorry about that. Kushal (talk) 00:04, 21 May 2008 (UTC)

No problem. :-) Ilikefood (talk) 00:19, 21 May 2008 (UTC)

It should be possible to find a PGP implementation for just about any operating system, even the old ones. --tcsetattr (talk / contribs) 00:56, 21 May 2008 (UTC)

PGP had an OS 9 client back in the day. Here's a interesting link that mentions what you need for OS 9 support. [4] --70.167.58.6 (talk) 19:57, 21 May 2008 (UTC)

Real-world computational complexity

Has any theoretical work been done on adjusting computational complexity theory for such real-world complications as:

• The time taken for disk and RAM operations
• The effects of swapping if there is insufficient free RAM
• The overhead costs of system processes and security software
• The optimal allocation of a limited upgrade budget

NeonMerlin 23:39, 20 May 2008 (UTC)

You don't need new theories to model these factors. Their modeling may require painstaking and tedious analysis, but is not very interesting from a theoretical viewpoint. --72.94.50.27 (talk) 02:33, 21 May 2008 (UTC)

Those things come into play very heavily during hardware and OS design, where paging and caching are very carefully watched to ensure they don't run wild. With that said, during application design, those factors don't typically affect runtime complexity, but may change the constant multiplicative factor. In other words, if an algorithm takes (3 seconds)*N^2 time in one case, and (5 seconds)*N^2 time in another (where N would be the number of elements of whatever we are operating on), it is O(N^2) both ways. Typically the worst-case or average complexity of an algorithm is what you pay most attention to, but when the constant factor becomes "very" large (e.g. Fibonacci heaps have notoriously large constant factors despite quite good theoretical runtime complexity) it might become an issue. From a more down-to-earth perspective, I think you'd optimize all factors independently to reach an ideal (or at least most cost-effective) solution: hardware, OS, and algorithmic logic. --Prestidigitator (talk) 04:34, 21 May 2008 (UTC)