Overclocking
Overclocking results for Athlon II X4 645 were unimpressive to say the least. Just over 3.70 GHz is not something you'd want to brag about these days, but keep in mind that these results are for reference only. More time and better cooling are needed to work around bugs and instabilities to find maximum stable clock.
Results were achieved using Scythe Katana 3 cooler, 1.465V on the core, and HT (base clock) of 240 MHz.