Design and Functionality
The heatsink represents the classic tower design with heat pipes and aluminum fins:
It measures 159 x 145 x 60 millimeters and weighs 710 grams. That’s not much for a heatsink, but the total weight of the Prime with its fan and fasteners is close to the 1-kilo mark.
The heatsink consists of 46 aluminum fins, 0.5 millimeters thick, which are press-fitted on the heat pipes 1.6 millimeters apart from each other. There is no soldering here, so the top fin looks as if it’s about to come off the pipes.
The total surface of the heatsink is 7260 sq. mm, which is average as tower-design coolers go. As for optimizations, we can note the hollows in the middle part of the heatsink formed by six groups of fins, five fins in each. The groups are separated by five pairs of fins with straight edges.
This must be meant to reduce the resistance to the air flow as well as to facilitate the uniform distribution of it along the heatsink surface. For the heat to flow uniformly in the fins, the pipes are positioned in a regular pattern.
There are a total of four pipes, each 8 millimeters in diameter. The pipes having a bend in the bottom part of the cooler, five of the bottommost fins have contact with only one pair of the pipes.
The Prime employs the first version of the direct-touch technology.
The pipes are placed 1.5 millimeters apart from each other in the heatsink’s sole. There’s an aluminum insert in the gaps between them. The sole is finished well and is absolutely flat. The thermal grease imprint isn’t uniform because our LGA2011 processor has a convex heat-spreader.
The Xigmatek Prime is equipped with one 140mm fan from the new XAF series. Its nine blades are curved like seaweed.
Xigmatek claims the new fan to generate 20% stronger air flow at 10% less noise, comparing it to some reference fan. The speed is PWM-regulated within a range of 800 to 1200 RPM. The maximum air flow is specified to be 90.3 CFM; the static pressure is 1.08 millimeters of water; the noise level is no higher than 18 dBA. We’d say that these specs are not what we can normally expect from fans working at such speeds. The fan’s impeller and motor are 130 and 40 millimeters in diameter, respectively. The cable is 300 millimeters long.
The fan runs on a sleeve bearing that features a copper core which is supposed to ensure a long service life of 40,000 hours at low noise.
The electrical specs of the fan are as follows: 12 volts (and a startup voltage of 9 volts), 0.30 amperes and a max power consumption of 3.6 watts. According to our own measurements, this fan consumed no more than 2.1 watts and started up at 5.5 volts. That’s good enough for a 140mm thing.
The fan is secured on the heatsink by means of two silicone bars that are fitted into the fan’s mounting holes and into the grooves in the sides of the heatsink.
Here is the Xigmatek Prime with the fan attached:
The heatsink being symmetrical, an additional pair of fasteners is included with the cooler to install a second fan. There is only one XAF fan in the product box, though.