360° View - Kingwin XT-1264 Heatsink Information on Frostytech's test methodology is available here.
The 120mm PWM fan on the Kingwin XT-1264 heatsink spins at 700-2300RPM. A standard 4-pin PWM motherboard header provides power. The heatsink stands 150mm tall and uses wire clips to hold the fan in place. A second fan cannot be installed. Looking at the back of the heatsink you'll notice that the two bottom-most aluminum fins have a spoiler to direct some airflow down towards the motherboard.
The side of the Kingwin XT-1264 heatsink is largely sealed, in this way the aluminum fins direct airflow flow through the 110mm tall, 48mm thick tower. Spaces are punched out at the bottom to make engaging the AMD clips easier - nice touch. The bottom-most fin is elevated 39mm for adequate motherboard component clearance. Each aluminum fin measures 0.3mm thick and is spaced 2.0mm from the next. The aluminum/heatpipe base is 10mm thick.
The base of the Kingwin XT-1264 heatsink is lightly sanded, the effective surface area measures 44x37mm. The four 6mm diameter heatpipes are swaged into the aluminum base block side-by-side, though nine aluminum peg-fins also rise up from the base plate and intersect ~30mm worth of fins above. The top of the XT-1264 has a false top to conceal the fact the four "U" shaped heat pipes are asymmetrical.

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 base of the Kingwin XT-1264 heatsink has a pressed and lightly sanded finish, with a surface roughness of approximately ~32 microinches. The base is flat in both axis and the copper and aluminum components are flush with one another.

Next up, sound measurements to determine how loud the XT-1264 heatsink is when operating at stock and reduced fan speeds.