Zalman's CNPS10X Quiet heatsink is equipped with a 120mm fan that ranges inspeed from 1400RPM to 700RPM, which in real world terms means that noise levels are moderate to whisper quiet. As a low noise heatsink the CNPS10X Quiet maintains good thermal levels on Frosty's AMD/Intel test platforms, and at full tilt it qualifies as a performance heatsink.