I says it is compatible:
Compatible with Socket 754, 939, 940 and the latest AM2 platforms, the Freezer 64 Pro will work flawlessly with most late-model AMD CPUs, including all AMD Sempron, Opteron, and Athlon 64, 64 X2, and 64 FX desktops.
A PWM chip keeps the 92mm fan running efficiently, with a volume of only 0.8 sone at 2200 RPM, which is tremendously quieter and more effective than the stock cooling fan.