My works at times, but then it randomly restarts during operation. Sometimes when it restarts it doesn't start up again, screens stay black and harddrives don't spin up (no beeps either). I have tried removing all the pci cards, the video card, the disk drives (hard and cd/dvd) the ram and tried reseating the cpu with no avail. I have also tried setting the bios options to default and optimal with no effect. The jumper switch for bios recovery mode doesn't seem to do anything either when the computer is dead. But then at times the computer works fine. Any suggestions?