Why does my desktop computer turn itself off after 20 minutes or so?

[Rabrrrrrr]

It's been like this for a couple weeks - it was working fine for a long time, and then, out of the blue, all of a sudden it has now decided that it needs to switch off after 20 minutes or so of being on.

I don't think it's a Windows problem, since it doesn't shut down via the software - the computer actually just switches off. Boom. No power.

But then, on powering up, it doesn't do a scandisk that one normally gets after a non-normative power down.

At first, I thought maybe it just the high heat, perhaps the power supply was overheating and it has auto switch-off when it gets too hot, since I wasn't running the air conditioning, but it does it even on cold days or when the air conditioning is on.

I did replace the power supply many months ago - but it has more power than the original one, and ran for probably 6 months without any problem whatsoever.

It's an eMachines desktop, running an AMD something or other, with Windows XP, standard American 120V 60 Hz AC. I've tried it in different plugs in the power strip with no change in behavior; and it's in the same spot, using the same outlet that it's used for 2 years.

I haven't installed any new software recently, either; I am very careful with web surfing and downloading, blah blah blah, standard safety precautions, blah blah blah...

It's really pissing me off.

[Gidney N Cloyd]

1. Reset it to a restore point from a few weeks ago and see if

stops doing that.

[Rabrrrrrr]

2. Sadly, I only have restore points from about 2003.

Unless it keeps automatic restore points.

[Gidney N Cloyd]

5. Should be automatically created unless you turn it off somehow

From the Help files:
"(restore points) are created daily and at the time of significant system events (such as when an application or driver is installed). You can also create and name your own restore points at any time. "

[Wcross]

3. Have you cleaned the fans lately?

Get a can of that compressed air and blow off the gunk on the fans. Look at the fins on the cpu cooling unit, there might be dust in there preventing proper cooling. It sounds like your cpu is overheating and shutting down the whole computer.

[Gormy Cuss]

6. Yep. That was why my PC was shutting down last year. n/t

[JesterCS]

7. This was my guess

overheating can guess resets and shutdowns.

[RevCheesehead]

4. OK, this might sound simplistic...

but you might have changed your energy settings... or perhaps your settings were corrupted in some way. You can check those through Display, under screen saver (at least, that's how mine works). :hi:

[jobycom]

10. Yeah, we should have asked if this happened while he is using it

or after he lets it sit for a bit. If his settings got changed to hybernate on a short cycle, that would cause what he's talking about. If it shuts off while he's using it, that's not the problem. But since it doesn't do a scan on restart, it does sound like it's hybernating or just shutting down.

[Maestro]

8. Like others have said

I vote for an overheating issue. Make sure the fans are clean, that cables inside the case are not restricting air-flow, and that all of your fans are operating including the heatsink or fan on your cpu and gpu (video card processor). Try to take off the cover and run the computer and see if that helps. If not, your computer is shutting down and secretly downloading porn! :)

[jobycom]

9. Power supply or CPU cooler. Check CPU cooler, first, it's cheaper

If there is a fan on the CPU, just take it to the nearest parts store, get a replacement for twenty bucks or less, get the heat seal pasty stuff, and replace it. EMachines is notorious for cheap components, and your fan may just be slowing down. Happens all the time at my work, where I maintain the computers.

The other possibility is the power supply. They go out easily, too, and if you buy a cheap-ish replacement, they are sometimes worthless. I've had a whole series of them fail in under six months. The worst ones don't even produce the power they claim. If it's built poorly, it can lose just enough power to shut you down. You can always return the power supply if that turns out not to be the problem--save all packaging.

This is part of my job, and anytime a computer does that at my work, those are the two things I do.

[Call Me Wesley]

11. Another possible thing:

There's an annoying program out there that bypasses the firewall/virus scanners and loads itself every time you start your machine, just to turn it off after about 20 minutes. So you can't really do a deep scan to find it.

Here's a nifty program:
http://www.majorgeeks.com/download3155.html

Download and run it, and save the log file. Feel free to PM it to me; if this program's on, I'll be able to help you.

[RetroLounge]

12. Perhaps it is just bored?

:shrug:

RL

[Hand]

13. Insh'Allah... nt

[Rabrrrrrr]

14. Thanks for the help everyone!

I finally had a chance to get into the computer - I vacuumed it out, and checked the fans. The fans were (and are) working; and there was very little dust.

So I don't know what was going on... but it's been on for almost an hour now, and no shut off, though I'm still running it without the side panel on, and it's not in its cubby hole.

I'm thinking that the cubby hole might not be offering enough air flow (though it's lived in the cubby hole for two years w/o a problem :shrug:)

[Xithras]

15. It IS a power supply problem.

Seen it a few times. What has probably happened is that your power supply has a cracked solder joint (happens all the time). When the computer heats up enough, the joint expands, opens up, and cuts the power flowing across the joint. It quickly cools, closing the crack and permitting the computer to be restarted.

There are two other possibilities, but I would assume that you've already checked the first, and the second is difficult to diagnose. First, have you checked that all of your internal connectors are on tight? If they're loose, you might be getting a lot of resistance which can trip the breaker. Easy fix, and I assume you've already checked. The second possibility is tougher...one of your other components has a mild short. This would eventually cause the breaker to trip in your power supply too. It's rare, but it does happen. The only way to test it is to disconnect a component at a time until it stops rebooting...and even that won't work if the short is in your mother board. This tends to be a difficult problem to tease out.

[Floogeldy]

17. I remember when my joint got cracked.

It wasn't pretty.

[Rabrrrrrr]

19. Fuck - I'm beginning to think that's it. After I posted my thanks,

about 3 minutes later the SOB shut off.

The power supply is a new one, that I replaced about 6 months ago.

I'm starting to think that I got a shitty one.

Though I'm also going to try a new power cord - one never knows, the cord might have a short in it: it's been sorely abused, and it is rather old.

[Xithras]

20. I've had them die quickly.

I once had a high quality power supply (Enermax) die in only a week. They are high power, high heat devices and they do have a higher failure rate than most parts.

BTW, if you had a short in your cord, it should be blowing the breaker in your house, not your power supply.

[Rabrrrrrr]

21. I'm thinking it might not be a short, just a broken wire

that would momentarily stoip conducting electricity.

it's a long shot, but worth exploring just to see what happens.

But I'm coming down more and more on the side of a shitty power supply.

[matcom]

16. it's infected with Bush's brain

only good for about 20 minutes then shuts down

[The Velveteen Ocelot]

18. Do you have a cat?

I've discovered that many computer problems can be attributed to feline interference.

Or maybe the computer just hates you.