This started randomly on a reboot. The system crashed and refused to start up again. This happened a while ago so I don't remember a lot of the details but I do recall that it at least reached the flashing questionmark (hard drive not found) on startup. The solution applied at the time was to install a new hard drive, which worked for a couple boots before the flashing questionmark reappeared. Are these hard drives ruined? Is there something else in the cpu possibly causing this problem?