I flashed my B2 Asus P8P67-M Pro with the B3 bios before I sent it back. It caused the EFI bios to basically stop working. It would not save most manual settings. They would all revert back to auto after reboot. The multiplier would not go past 43. One bonus it that it would boot and run @ 105.5 BCLK when 104 was the limit before flashing. YMMV