I've had great luck with the 0602 BIOS. I have had my e6600 up to 4.0GHz on this board and if the chip could do it, the board would easily go higher. One thing I learned is you absolutely have to up the voltage on the chipsets. I have both the NB and SB at 1.55v, just make sure you have adequate cooling. Also, set the CPU VTT to 1.5v. Make sure you turn off/disable any and all CPU controls.