Sir, I really think it's the HDD... I mean, I guess it could be the PSU... But.
Pies, Yeah, I'll look into that, Thanks! I'll post up some results, if I get them!
Also, I don't have anything spare that I could try...
Timo, I've left if un-plugged for like 12 hours and have it at stock and it still does it...
Thanks!
I think I may go ahead and buy a new HDD, I was after a new one before this all happened anyway..., so...