"The Coolage Freezer Orb heatsink is designed for Intel Core 2 Duo processors, and as with most heatsinks seeking to banish the stock Intel heatsink from the PC, it comes equipped with a Pulse Width Modulation (PWM) fan. Coolage's Freezer Orb F0-Z924AL heatsink is compatible with socket 775 Intel Pentium and Core 2 Duo CPUs."