plugged in or not I am going to take it to be repaired but I thougth I would ask you guys first. Personly I think it is a problem with the ram because i had the same problem when i built myself a pc a couple of weeks ago (I had put them in the slots in stead of 1in slot 1-a and the other in slot 2-a I put 1 in slot 1-a and the other in slot 2-b).
I havent changed any hardware and the problem started once when I put it into hibernation and then later tried to turn it on again).