PC Games Hardware reports German overclockers got their hands on three Phenom II samples and managed to overclock one of the chips to 5925MHz with LN2 cooling and the chip running at a voltage of 1.9V.
Thanks to extreme cooling they could even run benchmarks like the 3DMark 06 with more than 5 GHz. By their own account they achieved a "respectable result” with the overclocked Phenom II processor. The key to success were the low operation temperatures of partly under -190 °C.
"SoF"‘s CPU caused problems while overclocking under -160 °C because the used mainboard, Foxconn's A79A-S, missed an important function: The Phenom II processors only tolerate lowest temperatures if the HT clock is restricted to about 1,000 MHz.