PC switches off!!!

[SupaTek]

I've got P3 (1gz), 512mb ram, 80gb hard drive WinXP pro SP1.
It's been working fine for 3 years, until now.
The problem is that it switches itself off, it can be after 2 mins or 2 days of use. I've replaced the power supply and that got it working again for about a week, but now it's reverted back. Also checked for spyware etc and the bios settings and everything appears to be normal. There is no warning when it goes off (it's the same as turning the power off). Normally (but not always) I can turn it back on again. But sometimes the power light comes on, but the PC does not fire up.
Any Ideas?
Thanx

 

[Hipster Doofus]

If it is overclocked back it off. Failing that it could be the mother board or any other number of things. What's the temperature?

 

[enuffsaid]

Like Hipster said, it might be a heat problem. You can also try to replace your video card with a temporary one, and see if the problem dissappears.

 

[mlakrid]

Yep, prob a Heat issue... check your error logs, see if anything got posted...

 

[SupaTek]

I've had a closer look, and tapping the mobo in the area of the cpu, brings the fault on. It looks like a bad connection on the mobo.
I'll keep you posted.