I recently got a new PC. Windows 7 installs fine, and the first 2 hours everything runs perfect. then suddenly the computer reboots, but it's not a normal reboot, it loses all power ( as if someone had plugged it out), and then reboots. Checkdisk fails everytime and reboots the PC too. returned HD to seagate, they gave it back supposedly "repaired". changed RAM around, effects are the same. I think my mobo is broken, how do I check if it is?