computer turns itself off

[Jules]

My computer which has Win XP Pro turns itself off
whenever it feels like it. It's quite random and can be
hours or days apart. There's no pattern. I have checked
carefully and don't have a virus. I have turned off all
hibernate and screen saver options that would entice the
comp to shut down. My power light stays half on but I
need to turn the power on again to get my computer to
reboot. I don't get any 'you didn't shut down' msgs and
it's as if I didn't close a program (Outlook won't have
deleted my trash etc). Has anyone got any ideas?

 

[Rocket J. Squirrel]

Are you very certain that you don't have any type of virus or spyware, or
that you haven't adjusted any of your settings incorrectly? If so, then
suspect overheating or bad RAM.

Open the case and blow out the dust. Be sure that nothing inside the case
(particularly cables) impedes the flow of air. Determine if your fans are
running properly (or at all.)

If you have more than one module ("stick") of RAM, remove each in turn and
try your computer. Remember that you should be using exactly the same type
of RAM when you replace or upgrade.

Your motherboard may also be faulty.

Rocky