360° View - Coolermaster Hyper 612 PWM Heatsink Information on Frostytech's test methodology is available here.
The 120mm PWM fan on the Coolermaster Hyper 612 PWM heatsink spins at 600-2000RPM. A standard 4-pin PWM motherboard header provides power. The heatsink stands 163mm tall and is 140mm wide. The fan is held onto the 118mm tall aluminum fin stack with two plastic brackets. Additional clips can be used to secure a second fan if desired. With the fan removed you can see the line of heatpipes intersecting the aluminum cooling fins in a very straight line, spaced 12mm apart from one another.
The raw aluminum fins on the Hyper 612 PWM heatsink are press-fit over six 6mm diameter copper heat pipes which are soldered to a 3-7mm thick copper base plate. The bottom-most fin is elevated 43mm for adequate motherboard component clearance. Each aluminum fin measures 0.3mm thick and is spaced 2.0mm apart from the next.
The copper base plate of the Hyper 612 PWM heatsink is machined with a slight ridged texture and measures 36x44mm in size. Looking at the top of the heatsink we can see two smaller (black) aluminum fins which obscure from view the slits in the (raw) aluminum fins.

Base Finish and Flatness

Flipping a heatsink over to inspect the business end is often a simple indicator of overall cooler quality. More practically speaking, a heatsink is in many ways only as effective as the contact it makes with the processor - the flatter and smoother the better. Base finish is one of the criteria that Frostytech measure in the course of evaluating heatsinks, and it involves two distinct aspects. Surface Finish is the first; this is calculated with the aid of Surface Roughness Comparator that has a cross section of common machine surface finishes and their numerical surface roughness equivalents in microinches. The second is Surface Flatness. This is tested with an engineers straight edge or proven flat surface, in two axis.

The Coolermaster Hyper 612 PWM heatsink uses a 3-7mm thick machined copper heat spreader. The heatspreader is sparingly soldered to the six copper heatpipes judging by the gaps at the edge of each heatpipe channel. The copper base plate is very slightly concave in the direction parallel the heatpipes and very slightly convex in the axis perpendicular to them. Surface roughness is approximately ~32 microinches (ridged texture can be felt when fingernail run across the surface).

Next up, sound measurements to determine how loud this heatsink is at full speed...