Computer shuts down with no warning, then restarts

[Oogabob]

I am using Vista Ultimate and am on a fairly new computer, does anyone know
what is causing this? So far I have ruled out overheating and energy
problems. I set Vista to not automatically reboot and give me a blue screen
on crashes instead of autorestarting, but it still shuts down and
automatically restarts.

Is this a hardware issue? I've had problems with it doing this since I got
the computer, but it's seems to be getting worse.

 

[Peter Foldes]

Another leech post from vistahead hooking up to a 2 yr old post

 

[Ömer Coskun]

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