360° View - Scythe Fuma SCFM-1000 Heatsink Information on Frostytech's test methodology is available here.
Scythe's Fuma heatsink ships with a pair of 120x120x25mm PWM fans that operate at 1400-600RPM. A Y-splitter is supplied for motherboards which do not have dual 4-pin fan headers. The twin aluminum fin stacks each stand 103mm tall, 40mm deep and 130mm wide. Each aluminum cooling fin measures 0.3mm thick and is spaced 2.0mm apart from the next. The fins' leading and trailing edges have alternating straight and saw-toothed patterns.
The bottom-most cooling fins of Scythe's Fuma heatsink are elevated 34mm above the CPU for clearance. From the center of the heatsink base to the front of the fan measures ~77mm, to the rear of the heatsink ~55mm. There is an 8mm plenum in front of second fan and a ~3mm plenum between each fan and the 103mm tall aluminum cooling fin towers.
At the base of the Scythe Fuma heatsink we find a hefty nickel plated copper heatspreader liberally soldered to the heatpipes. The copper base plate is between 2-5mm thick and measures 38x43mm in size. Looking at the top of the cooler, we note the top two aluminum cooling fins are polished aluminum while the remainder of the cooling fins are stamped from standard, raw aluminum. This is purely for the sake of visual appearance. Heatpipes are arranged in a straight row, 17mm on center.

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 plate of the Scythe Fuma heatsink measures 38x43mm and has a smooth, machined surface finish. Surface roughness is approximately 16 microinches or better. According to the straight edge, the base is convex in one axis and flat in the opposite.

In case you missed the subtle reference to long term cooling reliability, 'Fuma' is the Japanese word for immortality. ;-)

Up next, acoustic sound measurements.