PC restarts itself

You're using W98 SE, I assume your machine is relatively new. If your motherboard uses Intel chip, Go to this site and find out why your machine is rebooting.

http://support.intel.com/support/mth/

Good Luck!

I have seen this happen several times. Everytime I have seen this problem
it has either been a faulty power supply or a bad processor. If you have a spare power supply that you know is good then replace the the power supply in your computer with the spare and see if that fixes the problem. If this does not fix the problem then if you have a good spare processor you can replace the processor in your computer with the spare to see if this fixes the problem.
The last time I saw this probelm I had to replace the processor. Hope this information helps you out.

I would double-check your CPU heatsink/fan.
It's my experience that a lot of times this happens something obstructed the fan, or it failed.

If the machine is still rebooting try a new CPU. Once upon a time, our store used Cyrix 6x86MX chips. (I know...eeewww!) Certain chips would just reboot. Put 'em on the RMA shelf.

Could also be a problem with the motherboard. Possibly a voltage regulation problem, maybe a cold solder joint coming apart.

Good Luck with it,

Tim

If you're using a Compaq, disable the advanced power saver in the BIOS. It may conflict with the Win power saver found in the desktop properties. Or contact compaq for a softpaq update (www.compaq.com).

I would definitely try checking out the processor cooling fan. It may be rebooting because the processor is getting too hot. Make sure you have a fan that is adequate for cooling the type of processor you have. If not, I suggest buying one that is...they are relatively inexpensive. Hope this helps. Good Luck.

Several good ideas already suggested, but replace the power supply first. That is probably it.

This is another possibility. Had a similar problem. Eventually discovered the electrical service would fluctuate every time a refridgerater compressor would kick on.(it was in another room but on the same circuit breaker). We put a ups on it. when it started beeping is when the fridge started. We then had the electrician gives us a dedicated line.

Make sure you have the latest BIOS and video drivers for your pc. Check the web page of your PC's manufacture to see if there are any known problems that would cause the reboot. It could be a faulty mother board.

The other responses are good ones, But here's three that weren't suggested:
First, if you have your computer hooked up to a powerstrip, try swapping with another powerstrip (APC network surge arrests work good), as it may be just "on the edge" and sagging somehow.
This Second is a bit more unusual and subtle - check in the bios to see if the thermal shutdown threshold temperature hasn't been set real low. (a user of mine *somehow* set his below 90 degrees, and was wondering why he had to turnup the air conditioning to keep the computer running longer...)
Third, make sure the power cord or the recepticle (on both ends) itself isn't intermitant with some kind of break in it that's picking up movement and disconnecting the power.

I almost forgot two other important ones that you'll need to crack open the case to find out - 1)Check to see if any cards have worked themselves partly out of a slot and maybe be disconnecting during vibration (I've seen this several times in a warehouse, the forklift goes by and the computer shuts down...)
2)I've also seen this on some Asus ATX style motherboards - Make sure there's no long cards extending right alongside the Cpu's heatsink and shorting out by touching the metal whenever thecomputer experiences movement or vibration.

i've read some of the answers to your ?. most of them really sounds good. all of them are thinking that it is a hardware problem. if you haven't resolved this issue try this instead.

Fast Shutdown Registry Key is enabled.
The Microsoft SystemCOnfiguration utility includes an option to disable Fast Shutdown. if this option is uncheked in Windows 98 SE, your system may reboot or shutdown. to resolve this issue, change the FastReboot value data from 1 to 0 in the following registry key:HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Shutdown

this is a longshot but, it might just help.

good luck,

if changing the power supply doesnt work, i would try a different motherboard. i just built a machine with the same problem, after i replaced the motherboard, it worked fine.