Asus P6T @ OC Club

"But both the 920 and P6T put on a little show and came up big. The maximum baseclock I could achieve with stability was 222MHz. But this was pretty much bench stable. 220 was stable enough to be prime stable at 220x18, or 3.96 GHz, pretty sweet so far. To get there I needed just 1.38 volts on the CPU, a QPI voltage of 1.39v, IOH of 1.36v, CPU PLL voltage of 1.86 with the memory at 1.62 volts."