360° View - Arctic Cooling Alpine 11 Pro Heatsink Information on Frostytech's test methodology is available here.
The fan is arguably the most important aspect of the Arctic Cooling Alpine 11 Pro heatsink. It is supported by four rubber posts which connect to the motor body. The 7-bladed fan spins quiet at full speed, utilizing special Fluid Dynamic bearings. Default fan speed is 2000RPM, the lowest rate is 500RPM. Power is supplied via a standard 4-pin PWM motherboard connector. Each extruded aluminum fin measures roughly 32x98mm in size. Each fin is 1.0mm thick and spaced 1.5mm apart.
The 95mm fan intakes air from above and blows it down into the aluminum fins below. The warm exhaust air then exits at either side of the heatsink where it can cool the northbridge chipset for example. The Alpine 11 Pro's heatsink retention mechanism is dead simple, a plastic bracket attaches to the motherboard and then two screws applying clamping pressure by locking into the bracket.
The effective base area of the Arctic Cooling Alpine 11 Pro heatsink is 64mm x 40mm in size, it has a sanded finish and comes with a pre-applied patch of grey thermal compound. The aluminum is generally flat, but not perfectly so in either axis.