Random crashing

[roughlad]

I have a pc that keeps crashing at random times.
I have taken out hd and used a live cd- crashing trying to load live cd will sometimes work fine.
ran memtest- no error's
diffrent psu- still crashing at random.
The pc takes ages to switch on which may or may not be related (cold room)

Specs:
P4
msi rc410m mobo
cheap generic ram.


Does anyone have any ideas?

 

[Skilid]

How long did you run memtest for?

What sort of crashing? Just locking up? Or rebooting?

I think it'll be either memory or motherboard.

 

[SupermotoMX]

im thinking its the ram / motherboard also