random power down problem

[Clark the White]

Hi folks,

I've remembered my password for the forums woot!
please can anyone help me I've built a new system for myself which is working perfectly, but my old system randomly powers down between 10-60 seconds. does anyone have any ideas because I'm stumped!

I've tried 3 different psu's and it still keeps doing it so its not the psu. I've replaced most other components which makes me think it's the motherboard, but if so why would it power down randomly instead of instantly? I would have thought being as it never gets to boot windows and does the same thing every boot it would power down (switch off) at the same point everytime.

I know I had to replace the capacitors on my mobo before so could it be that again do you think? although last time when they went my machine would not boot at all -I'd get a c3 error, but this time, is it possible the part of the mobo which regulates the power from the supply is dodgy?

my old motherboard is a Epox 8rda+ running an athlon xp2600+.

I do have another spare socket A motherboard but I'd rather not have to completely change mobo if I don't have to so I thought i'd ask first.

Thanks for any help people