Computer restarts at random

My computer restarts at random times. I can't tie it to anyone specific program. It will restart sometimes after a couple minutes and sometimes after 20. There is no error message whatsoever. I unchecked restart on BSOD but I still get no error message. Recently the CPU fan began making a lot more noise than usual. It will get real loud during boot up or anytime I run a program. I tried running a game and it stayed loud the entire time the game was running. I have anti-static grounding equipment and I opened the case and it doesn't seem hot at all so I don't think it's overheating, but I don't know for sure. I did have some malware on the computer but I just got done posting that on the malware forums and the computer reads clean now. Any help you can offer will be greatly appreciated!

Thanks in advance,
jrhall

 

It does sound as though this is an overheating problem.
As a test, place your computer in as open an area as possible (to maximize air flow) and (if it is a desktop rather than a laptop) remove the case cover.

If this is a laptop elevate it by place something underneath each side of the computer (taking care not to block any ventilation ducts)

If the problem lessens of goes away entirely, replace the CPU fan.

 

You can download and install temp monitoring software to see if it is a heat issue.

I've used HWmonitor and like it. http://majorgeeks.com/HWMonitor_d5842.html

Your BIOS will generally show temps as well, you might want to see what temps it is showing.

Since you said you've already opened the case, I'm assuming that you've already made sure that dust has not built up in the heatsink or on the fans. Dust can cause a lot of problems in a computer, including heat issues and fan problems.

 

If it were overheating, it would shut down not reboot. I'd test the power supply to see if that might be marginal.
You would also get random error messages if a stick of RAM was going bad; so I'd also test the RAM.

 

If you have more than one memory module installed, remove one and run the machine to see if the problem presists. If it does, remove the installed module and replace removed memory. Trying to determine if you have defective or miss-matched memory.

 

In addition to plodr's and Carolina's suggestions, I was also thinking it could possibly be a hard drive problem. Run a full diagnostic using the manufacturer's utility; you can download it for free from their web site....

 

I tried running it for a couple days now on my kitchen table with the cover off the case and it hasn't restarted once. So I went out and bought a new heat sink/fan and thermal grease before I read the rest of the replies. I haven't had a chance to install it yet, but hopefully that fixes it otherwise I'll continue with your suggestions. Thanks a bunch!

jrhall

 

Ok the computer did fine for a couple days now it seems to be restarting again althought I don't think as frequently. I'm not sure what that means. It only has one stick of memory, and I don't know how to test the power supply? I'll try and download the diagnostic program for the harddrive.

jrhall