Wikipedia:Reference desk archive/Computing/2006 August 28

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[edit] Boot-up Problems

Recently, my cooling fan has gone to its max speed when I have been attempting to turn on my computer, and then it fails to boot. Does anyone happen to know what might be causing this? It seems to be a hardware issue and not a software one. I am really frightened because if this computer dies, I won't be able to get another one. --Demonesque 02:18, 28 August 2006 (UTC)

What do you mean by "fails to boot"? Does it even get to the POST (that is, the nice happy screen when the computer first starts and does memory tests, etc.) Does it make any beeping sounds? -- Consumed Crustacean | Talk | 08:04, 28 August 2006 (UTC)
I own a Dell laptop and when I updated/flashed my BIOS, the fans ran extremely fast at startup, then it booted with the new BIOS. Though this is just speculation, there could be something wrong with your BIOS, which is not good at all. --Russoc4 11:56, 28 August 2006 (UTC)

I don't get anything on my monitor. It just remains black. I don't get any screens.

If it is my BIOS, what can I do about it? --Demonesque 20:30, 28 August 2006 (UTC)

I seriously doubt it's your BIOS, though it's mildly possible. More likely, it's a motherboard or CPU issue. The power supply might almost be ruled out because it's getting as far as it is, though it's still possible. The best way to diagnose this would be switching the power supply with another computer's, and if that fails then going through each of the other components. If you don't have spare parts laying around, or don't know how to take a computer apart (not too difficult), then you may be out of luck :/.
Other possibilities: try dusting the thing (compressed air), especially around the fans. Try taking the RAM and cards out, and then putting them back in securely. Look at the capacitors on the motherboard (they stick out); if they're leaky or bulgy, it's no good. -- Consumed Crustacean | Talk | 21:55, 28 August 2006 (UTC)

I did open it up when the problem first occurred, since it seemed, as I said, to be a hardware issue and not a software one. The thing is, though, that I have no clue about the hardware side of computers. I was just looking to see if there was an obvious cause like a melted processor or capacitors. It is a bit dusty in there but I ran out of compressed air a while back. However, there isn't much dust.

I have had someone else suggest that my power supply might be faulty when my hard drives fried about a year ago. I would have no idea how to remove and replace it, though, nor do I have another computer to switch parts with. As I said, if this computer goes, I'm out of luck and will have to buy a really, really cheap and crappy one. My current system has 1022 Ram, 3.60 GHz and about 230 Gigs of useable hard drive space, so it would be the end of the world for me to lose it. --Demonesque 01:44, 29 August 2006 (UTC)

[edit] Internet Cafes

How can I get access to a precise business plan for operating an Internet cafe in a resource-poor community of Africa? Richard Bugembe

That is a business question, not a computer question. However, there is no such thing as a generic business plan. You have to go to the area, estimate every single cost you will have for the first three years, estimate every single profit you will have in the first three years, and if your estimated profits exceed your costs, you have a business plan. For most people, getting a loan on their plan fails because they just make up the numbers and have nothing to back their estimates. So, you have to actually do work by running surveys, asking neighboring businesses about their expenses, getting quotes on construction, design, services... You cannot just steal someone elses plan and hope it works for you. --Kainaw (talk) 12:30, 28 August 2006 (UTC)
I can't see how an Internet cafe could be profitable in a resource-poor community in Africa (which means poor area, I assume). Only wealthy areas in Africa could support such a business. Now, if you want to set up a charity which provides Internet access to the poor in Africa, that might very well be possible. The greatest expense seems to be hiring personnel to run the place. Somebody experimented with another concept in a poor area of India, where they just left a computer on in a community center and the kids seemed to learn how to use it on their own, eventually, and then taught others. StuRat 03:54, 29 August 2006 (UTC)

[edit] C programing

"Write a program in which we find a temperature from celcius into Ferenhight at the run time in C programing language? so that we enter the temperature in celcius and after processing it give us in Ferenhight"--82.148.119.152 16:42, 28 August 2006 (UTC)

No. However, I will point out for your benefit that the fractions involved in the conversion should not be written as (for instance) (3/7) in the code, because that will evaluate to 0 in C. Use a type conversion, or write your numeric literals as floating-point. I'd also recommend looking up Celsius (note spelling) for assistance with the math. --Tardis 17:31, 28 August 2006 (UTC)
I'll write the program if you pass on the grade to me. --Kainaw (talk) 18:37, 28 August 2006 (UTC)
That seems fair. Even so, ethics require that the instructor be informed. Would it be acceptable to give a partial program in Scheme?
(define C2F (lambda (C) (let ((r 1.8) (e -40.0)) (+ e (* r (- C e))))))
(Correctness not guaranteed!) Or would that be giving away too much? ;-) --KSmrqT 22:27, 28 August 2006 (UTC)
°F = °C × 1.8 + 32
There you go! Now just write it in C. Ohanian 22:25, 28 August 2006 (UTC)
And while you're at it, if you're using a command line interface, you'll need to access some functions in the C standard library to get the input and print the output. The functions that deal with input and output are in a header file called "stdio.h". Good luck! --Robert Merkel 22:59, 28 August 2006 (UTC)

[edit] Trusted paths outside of Windows

Oddly enough, to my knowledge Windows is the only OS that provides a reasonable trusted path for user password input (the famous "Press Ctrl-Alt-Delete to begin."). Why aren't such things implemented on common varieties of Unix, or on the Mac? (Or if they are, what are they?) Some things come close, like the common Ctrl-Alt-Backspace that kills many X servers, and the almost-always-present menubar in Mac OS X, but none of them appear to actually be unforgeable. I recently had the idea that a graphical login screen could display some sort of shared secret (e.g., the contents of a file only the user can write and only root can read) to a user (as some websites do as an anti-phishing measure), but there's no way I can see to prevent Mallet from attempting to login as Alice, grabbing her secret (even if it's dynamic), and then displaying that to her with the fake login screen. Is there some way to salvage the idea? --Tardis 17:49, 28 August 2006 (UTC)

See secure attention key. It is available in Linux, just not packaged with normal distributions. --Kainaw (talk) 18:36, 28 August 2006 (UTC)

[edit] Computing/IT

Would you consider dropping the 'IT' part from the header? It would make it easier to archive/transclude, since the subpage would be the same as the title--71.247.243.173 18:57, 28 August 2006 (UTC)

  • btw, when I say 'you' I pretty much mean any CS desk regulars who might have a preference for one particular title--71.247.243.173 18:58, 28 August 2006 (UTC)
*Wikipedia:Reference desk archive/Computing/2006 August 7

vs

*Wikipedia:Reference desk archive/Computing/IT/2006 August 7

The output from the new template, would create an un-needed subpage, or even worse, will simply confuse people, and cause the next day headers to simply red link, if the tagging isn't done consistently--71.247.243.173 19:07, 28 August 2006 (UTC)

Or, you can use Computing&IT. --Kainaw (talk) 19:31, 28 August 2006 (UTC)
The point is not to get rid of the subpage, rather to make the subpage: computing have the same name as the desk: computing/IT. Making it Computing&IT is only helpful if you want to move this page to Wikipedia:Reference desk/Computing&IT--71.247.243.173 19:47, 28 August 2006 (UTC)
  • If we go back to the old system, we have to go back to the old template, that needed 5 separate inputs to create each transclusion header. The new version only needs 2 unique inputs in order to work, but it requires that {{{Type}}}="computing"=archive name--71.247.243.173 19:53, 28 August 2006 (UTC)

Basically, the transclusion process is unnecessarily involved. I'm trying to streamline it, to make people more able to volunteer to do the work, since we still don't have a bot. One of the changes, requires that CS desk transclusion use the word Computing by itself, as a title, since it shares a variable with the line that generates a link to archives from the day before. This desk is unique in that respect, since it is the only desk to have a title that is different from it's pagename--71.247.243.173 20:12, 28 August 2006 (UTC)

[edit] Bad, invincible, double-redirect-fixing bots

Have bots been written to resolve double redirects? Do I no longer need to fix these? --Username132 (talk) 21:50, 28 August 2006 (UTC)

You seem to have already found the place for this sort of question: the Help desk is your best bet. — QuantumEleven 05:50, 29 August 2006 (UTC)
They havn't answered it though... I recon the people that frequent this desk are more likely to be suitably informed regarding the bot operations on Wikipedia. I just don't want to waste time fixing things that will be fixed by a machine. --Username132 (talk) 11:17, 29 August 2006 (UTC)

After some searching, the answer is yes - bots do exist to perfom this operation. We need do it ourselves no more. Wikipedia_talk:Computer_help_desk/double_redirect_study - should I edit the double redirect help page accordingly? --Username132 (talk) 11:24, 29 August 2006 (UTC)

[edit] VGA and DVI: connecting a monitor to a PC

After reading through the respective articles (DVI and VGA connector) I have one unanswered question which I hope you wizards of the computing ref desk could help me with: If I understood correctly, the DVI connector carries both analog and digital signals (although compared with the 15-pin VGA connector the I²C signal seems to be missing). Could I connect a monitor with a VGA connector to a PC with a DVI output (using an adapter of some sort)? It seems like this ought to work since the same signals are present. Obviously the digital signals in the DVI connector would go to waste. Would it work as well as on a computer with a VGA output (I am thinking particularly of the 'missing' I²C analog signal in the DVI connector)? Thanks muchly in advance! — QuantumEleven 22:19, 28 August 2006 (UTC)

It does work. Many video cards, including all of the ones which I own, come with a simple adapter that does this. You can likely pick them up at a local electronics store for a small price. From what I've seen with my own eyes, and from what I've heard others say, there is no quality degredation in DVI->VGA compared to simply VGA. -- Consumed Crustacean | Talk | 04:52, 29 August 2006 (UTC)
Thanks muchly! It seems that the video card (with only DVI output) already includes one of these adapters, so all is well. Cheers! — QuantumEleven 11:44, 30 August 2006 (UTC)