The 9-bladed 120x120x25mm PWM fan on the GeminII S spins at 1000-1800RPM. With it removed, the frame for attaching a special bracket allowing two 92mm or 80mm fans to be used on the Coolermaster GeminII S is visible. Note how the widely spaced aluminum fins over the base of the GeminII S go all the way down and contact the copper CPU base plate below.

The Coolermaster GeminII S heatsink is not very tall, just 88mm in height. There is 37mm of clearance on one side for things like memory slots, and with the extender bracket two fans can be mounted so one partially overhangs the DIMM slots. The nickel plated aluminum fins are 0.3mm thick and spaced 1.5mm apart. A section of fins 35mm wide is soldered to the 6mm thick copper base of the heatsink directly.

The copper base of the Coolermaster GeminII S heatsink measures 37.5x38mm in size, and is machined perfectly flat. Five 6mm diameter copper heatpipes are sandwiched between the 6mm thick copper base plate and aluminum fins above. The heatpipes fan out from the base evenly over the entire 120mm width of the heatsinks' fins.