F9 bios is working great with P35-DS4 rev 1.0 Actual voltages are now in bios and there is also option for loadline calibration. With it enabled I could clock higher than bios F6. Also noticed that now cpu-z shows 1.520-1.536V load when 1.575V set in bios With bios F6 cpu-z showed 1.504-1.520V when priming.