360° View - Nexus VCT-9000 Heatsink Information on Frostytech's test methodology is available here.
A single 120mm PWM fan is mounted on the VCT-9000 heatsink, angled back at 25 degrees. The fan spins at 1600-500RPM and draws power via a standard 4-pin PWM motherboard header. Four 6mm diameter copper heatpipes and one 8mm diameter copper heatpipe connect the fin stack with the base of the cooler. The heatsink's total height is 153mm, the distance from the CPU to the lowest fin is 39mm.
The fan is angled back 25 degrees and the depth of aluminum fins changes from 78mm at the bottom to 35mm at the top. Each aluminum fin measures 0.3mm thick and is spaced ~2.0mm apart. At the base is a small ~20mm skived aluminum heatsink.
The base of the Nexus VCT-9000 measures 36x51mm. Four 6mm diameter copper heatpipes and one 8mm diameter heatpipe are left exposed with a rough sanding finish. This base plate was not flat on the heatsink Frostytech tested, only the first and fourth heatpipes made good contact with the CPU test die due to the general unevenness.

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 exposed heatpipe base of the Nexus VCT-9000 heatsink is good a lesson in how not to make an exposed heatpipe base heatsink.

The four 6mm diameter heatpipes and one 8mm diameter (center) heatpipe are loosely kept in the nickel plated aluminum base cap, with large voids visible everywhere. Lateral heatspreading is hampered, to say the least. More importantly, the five heatpipes are not even with one another and slightly convex in the axis parallel to the direction of the heatpipes. This causes two heatpipes to make contact with the CPU die while three remaining heatpipes are elevated a fraction of a millimeter higher. To add insult to injury, the heatpipes have been unevenly sanded to a surface roughness of approximately ~48 microinches.

Next up, Frostytech's acoustic noise level comparison.