Design and Functionality
Prolimatech Megahalems is tower-heatsink measuring 130 x 74 x 158.7 mm and weighing 790g. The heatsink sits on six copper nickel-plated heatpipes 6mm in diameter that go through a copper nickel-plated base.
The heatpipes hold two aluminum heatsink arrays with 5mm gap between them.
According to the manufacturer, the heatsink was designed of two separate arrays in order to reduce the resistance to the airflow from the fan and not to eliminate the “dead zones” in the heatsink, as you may have thought in the beginning. For the same exact reason the heatpipes inside the heatsink are all lined up. As a result, Prolimatech engineers can claim that their cooler is optimized for fans with 800-1200RPM rotation speed, although it is not quite so in reality. Moreover, having heatpipes lined up into a single line doesn’t ensure even heat distribution over the heatsink plates. As a rule, coolers with design like that yield to their competitors with more optimal heatpipes positioning.
Each heatsink array consists of 45 aluminum plates, each about 0.5mm thick:
The heatsink has a total of 90 plates, so its calculated effective cooling surface taking into account all the curves, sides and heatpipe holes makes 7008 sq.mm, which is a pretty average size for contemporary cooling systems.
If you take a closer look at the cooler, you will see that the heatpipes do not pierce the heatsink plates, but the plates each consist of two halves that are soldered to the heatpipes and clipped together on the sides:
Of course, this contact method does have an evident advantage over traditional one, when the plates are pressed against the heatpipes piercing them. Since the plate is cut in half, there is no need for technological holes, there is bigger contact area between the heatpipes and the plates, and hence the cooling efficiency increases. Besides, Megahalems has pretty thick heatsink plates, so it could be pretty hard to press them against the heatpipes tightly enough.
We also noticed that the manufacturer tried to bend the heatpipes as little as possible making sure that there is no additional resistance to the heat flow inside the pipes.
They resorted to soldering technique not only for the heatpipes and heatsink plates, but also for the heatpipes and the base of the cooler. You can clearly see solder traces on the sides of the base plate:
To ensure the most effective heat transfer, the heatpipes have been put into special grooves in the base plate. The thinnest part of the plate beneath them measures 3mm.
The base finish quality leaves much to be desired; there is no polishing of any kind. Moreover, you can feel the machine marks if you touch the base plate surface.
However, it is not as important as the evenness of the cooler base. Let’s check it out now:
It turned out that the base of the Prolimatech Megahalems cooler we got for review is slightly protuberant and one of the four corners is dropped by about 0.25mm. Despite these observations, the thermal compound imprint on the CPU heat-spreader turned out quite satisfactory: