One of the BSODs could have corrupted OS. Is repairing the OS an option / have you tried it already? If so, I would recommend an OS reinstall so we can move on and see if this is a hardware issue.
Before reinstalling the OS, though... I would recommend resetting all overclocks (if any) to stock via the BIOS and trying to boot again to make sure this isn't an unstable overclock
Edited by pjBSOD - 4/6/12 at 9:06pm