Wow, same story as me. I'm stuck with the problem nearly 2 week. For me, the problem was with the cpu thermal pad. It got damaged somehow.(I touched the heat sink to hard??).Dissembled the heatsink and I discovered that the CPU and Northbridge which share the same heatsink have a different height. They put a thermal pad on the cpu side. I came here because I wonder if anyone else had the same problem(which should happen because of the bad design).
Try check yours(maybe it will void your warranty). I replace mine with Artic Silver thermal paste and I remove the brown barrier at the cpu side to make sure it touch the cpu.
piXca.net back from the death
Before I find this, I thought bios was buggy. Have done hundred of bios reset with no luck. Hope it help. Good luck.
p/s: support center s**k they never replied my mail.