Hi I keep getting the problem where my PC will boot up fine, but then randomly turn itself off, usually during heavy processing but not always.
Windows XP loads up fine, and I have tried it with a separate HD with a different install, so it is not a software problem or the Hard Drive.
Havent installed any new hardware recently.
Replaced the PSu, thought that would help, but it didnt.

When the PC turns itself off, it is instant, as if someone flicked the power switch at the back. To turn it back on, I have to switch it off at the back for at least 30 seconds otherwise nothing happens.

The LEDs on the front of the case dont light up anymore either, dont know if thats anyhting to do with it.

So how can I sort this? Thanks in advance,

G