360° View - Zalman CNPS9500 AT Heatsink Information on Frostytech's test methodology is available here.
	The Heatsink Fan: The 92x92x25mm fan spins at 1350-2650RPM with the aid of a PWM-capable Intel motherboard BIOS, producing 18-27 dBA according to the companies data. The lack of any fan guard presents a challenge for systems with many loose wires dangling around inside the case, and the CNPS9500 AT's height of 126mm precludes it from being used in compact or SFF-PC cases. The fan draws power from a 4-pin Pulse Width Modulation (PWM) motherboard fan header. It is also backwards compatible with 3-pin fan headers. When connected to this variety, the Zalman CNPS9500 AT heatsink automatically defaults to full speed mode after 5 seconds if now PWM signal is present.
	Heatsink Top: The Looking down at the top of the Zalman CNPS9500 AT heatsink we can see the basic shape of its 88 copper fins. The 9mm wide indentation at the center provides space for a screwdriver further down when engaging the heatsink clip onto the CPU retention bracket. The clip fits in perpendicular to the direction of the heatpipes. Each fin measures just 0.2mm thick. Fins are spaced 3mm at the tip, and 1mm along the inside curvature. The copper fins are all soldered directly to each of the three copper heatpipes.
	Heatsink Side A: The 92mm fan is suspended in the center of the radial fins and figure-eight heatpipe assembly on a pair of stainless steel posts. When powered up, vibration were not noticeable. The space directly behind the fan motor is empty, which makes sense as this is generally a dead-spot for airflow. The Zalman CNPS9500 AT heatsink installs onto socket 775 processors with a stainless steel clip that fits over the nub of the cast aluminum base, and a special retention frame that mounts to the motherboard directly. The clamping force is focused directly at the center of the heatsink's base, for even loading on the processors' integrated heat spreader.
	Heatsink Side B: Every side of the 530 gram Zalman CNPS9500 AT heatsink is made for cooling as we can see from this image. The cooling fins extend out to a diameter of 112mm. Each of the three copper heatpipes are 6mm in diameter. The base consists of a shaped copper section to which the heatpipes are soldered, and a base cap made from cast aluminum. The copper base is about 2.5mm thick on average, 4mm at the most.
	Heatsink Base: The The 38mm x 40mm copper base is soldered to the heatpipes so thermal conductivity is direct as possible through to the rest of the heatsink. The copper base has been machined flat, and very smooth. Surface roughness is on the order of ~12 microinches, which is considered very good. The aluminum cap actually hovers about 0.8mm above the heatpipes, instead of coming in direct contact with them. The result of these optimizations is a base which is quite flat in both axis.