360° View - DeepCool Neptwin Heatsink Information on Frostytech's test methodology is available here.
DeepCool's Neptwin heatsink ships with two 120mm fans arranged in a push-pull configuration. Additional wire fan brackets are supplied to attach a third fan on the rear of the heatsink, but this is impractical for most motherboards due to space issues. Each aluminum fin measures 0.4mm thick and is spaced 2.0mm from the next.
The six 6mm diameter copper heat pipes are sandwiched between an 8mm thick aluminum base cap and 5mm thick copper plate at the base. The two fans are held in between the 102x120x40mm aluminum fin stacks with springy wire fan clips (with thumb tabs. There's only a 2mm plenum in front of the middle fan. The bottom-most aluminum fin is elevated 46mm above the base of the heatsink for clearance.
At the business end of the Neptwin heatsink there are six 6mm diameter copper heatpipes soldered to a 5mm thick slab of nickel-plated copper. The base measures 39.5 x 50mm. Looking at the top of the heatsink, we see the heatpipes are spaced 10mm from each other in a straight row.

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 engineer's straight edge or proven flat surface, in two axes.

The nickel plated copper base of the DeepCool Neptwin heatsink is flat in one axis and very slightly concave in the opposite. The polishing and subsequent metal plating leave it with a mirror smooth surface; surface roughness can't be greater than ~8 microinches.

Up next, heatsink sound level comparisons....