Design and Functionality
On the outside the cooler reminds us of the Arctic Accelero Xtreme: there are three cooling fans that cover the entire heatsink:
However, the differences stand out immediately: the fans are of different diameter. There is a 90-mm fan in the center and two 80-mm fans on the sides. The actual impeller diameter is 86 and 73 mm respectively.
The cooler measures 260x103x52 mm and weighs 555 grams. This makes Spire SkyMax a little mode compact and lightweight than the recently reviewed Arctic Accelero Xtreme 7970. The fans are fastened inside a plastic frame, which clicks to the sides of the heatsink:
The heatsink itself is a two-array one. Each array consists of 0.3 mm thick aluminum fins pressed against the heatpipes with 1.8 mm gaps between them:
The arrays are not identical. The larger array consists of 62 fins and sits on two heatpipes. The smaller array consists of 48 fins on three heatpipes. In our opinion, it is not the best solution, because the larger array is capable of dispersing more heat and it should have been pierced by three heatpipes instead of two, as they did it. However, they must have been guided by the peculiarities of the heatpipes layout in the cooler base, because all of them come out on the same side and run across one another:
The heatpipes are 6 mm in diameter. It seems like there is some thermal glue involved in the contact between the heatpipes and the 70x40 mm base plate. However, we found neither traces of thermal glue, nor traces of soldering anywhere on the base: the contact area is exceptionally clean and neat.
The base surface is finished nicely. There is no mirror-polish, but the surface is perfectly even – the GPU die left an ideal thermal paste imprint on the Spire SkyMax base:
I would also like to add that there is a small aluminum heatsink directly above the heatpipes in the cooler base area. It is designed to take the heat off the top of the heatpipes.
Spire SkyMax is equipped with three fans, two 80-mm fans and a 90-mm central fan:
The fans rotation speeds are automatically adjusted using PWM method in the interval from 1300 to 2800 RPM. They may be connected directly to the graphics card via a three-pin connector as well as to a PATA connector of the power supply. In the latter case the rotation speed will not be adjustable any more. The slide bearings inside the fans should last at least 30,000 hours or over 3.5 years. The measured start-up voltage is 5.1 V and the total power consumption of the three fans equals 8.9 W.