Its NOT a graphics card issue! Madness. I reinstalled my old card last night and it is still powering out and rebooting of its own accord. (Even with my new 400W PSU) Interestingly enough, it has happened most when using Evidence Eliminator, which is quite a thorough disc scouring program.
I wonder. Could someone please tell me what are the signs of a 'dead disc', or at least a dying one. Are the symptoms above, testament to a dying disc? And if not, what in the hell is going on in there?!