360° View - Xigmatek Prime SD1484 Heatsink Information on Frostytech's test methodology is available here.
The 140mm PWM fan spins at 1200-800RPM and draws power from a standard 4-pin PWM motherboard fan header. Notice how the fan is much larger than the aluminum fin stack. Each of the four 8mm diameter copper heatpipes extends from the base where it is exposed, to the top of this 167mm tall heatsink. Each aluminum fin measures 0.5mm thick and are spaced ~2.0mm apart.
The Xigmatek Prime SD1484 heatsink stands 167mm tall, the tower is 62mm wide without a fan and the first fin is elevated 43mm above the CPU socket for clearance. Heat pipes are positioned 9mm on center at the base plate and rise up apart 48mm and 91mm respectively. The base incorporates an 11mm thick aluminum section to provide support for clamping.
The usable area of the Xigmatek Prime SD1484's exposed heatpipe base is 42x42mm in size. Heatpipes are positioned in the path of highest airflow from the fan, the rubber bracket tends to bend in the top and bottom-most aluminum fins a little.

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.

Most exposed heatpipe base heatsinks are machined flat, the Xigmatek Prime SD1484 is not. Instead of a precision base it has a sanded base surface finish which is somewhat convex in both axis. The surface roughness of the base is approximately 16 microinches, which is considered good.

Next up, Frostytech heatsink sound level measurements...