"Thermaltake's ISGC-400 is a lower noise low profile heatsink suitable for media PC or other compact chassis. The aluminum cooling fins on the ISGC-400 are widely spaced to allow air from the single 120mm fan to pass through easily, so a high speed fan isn't needed. Six 6mm diameter copper heatpipes ensure good thermal conduction from the base to the saw-toothed fins and a small manual fan speed controller attached to the fan power cable allows fan speed to be adjusted from 800-1300RPM for situations which demand the least noise possible. "