PCs been stable for about two weeks now at it's current speed (check sig) and lately its started randomly rebooting itself. I can run orthos for days on end and no errors in memtest. The weird thing is that the PC tends to reboot itself when I'm not doing anything. Like when I first start it up and am waiting for the startup programs to load, but If I click and open anything else during this time the PCs fine. Mind you that it doesn't restart all the time, just occasionally. Could this be a hardware failure or what?