360° View - nPowertek SF775-2 Heatsink Information on Frostytech's test methodology is available here.
	The Heatsink Fan: The nPowerTek SF775-2 heatsink is built with a 92mm diameter fan. The 7-bladed impeller on this Pulse Width Modulation (PWM) fan spins at speeds of 0-4200RPM when controlled by the computer's BIOS. Power is supplied by the 4-pin PWM fan cable which connects to a standard 3-pin or 4-pin motherboard fan header. The fan defaults to its full speed when the PWM-signal is absent. There is a 9mm plenum between the top of the copper fins, and the bottom of the fan impeller to promote even airflow distribution within the radial structure.
	Heatsink Top: 136 copper fins wrap completely around a 31mm diameter copper column. Each fin has a slight counter-clockwise curve to it, and is soldered at the base with 0.75mm tab. The copper fins measure 0.2mm thick and are spaced 1.5-2.0mm apart along the outer edge. The entire body of the nPowerTek SF775-2 heatsink has a diameter of 88mm. Notice the four spring-tensioned mounting posts at each of the four corners, the bottom of that support clip obscures a portion of the exhaust space.
	Heatsink Side A: The nPowerTek SF775-2 heatsink stands 36mm tall, and the heatsink has an overall height of 62mm. The spring tensioned mounting screws affix to the rear mounted metal support bracket. Notice the clear plastic fan support frame, it holds the fan in place at center above the cooling fins.
	Heatsink Side B: Air is exhausted dow and out from the copper cooling fins, where it can then be used to cool adjacent board-mounted components. Most socket 775 Intel motherboards are designed to use this source of airflow, and so VRM and chipset heatsinks are often entirely passive.
	Heatsink Base: The copper base of the nPowerTek SF775-2 heatsink is 41mm in diameter where it makes contact with the CPU integrated heatspreader. The copper has a pressed and sanded finish, and is pretty smooth to the touch. The surface is wavy in both the x and y-axis. Surface roughness is on the order of ~32 microinches, which is considered good. Since the mounting hardware screws into the base of this heatsink, it's safe to assume a K8 version is also available from the manufacturer.