Page 2 - Physical Look - Hardware; Installation
The DeepCool AK620 is a clean and simple looking cooler with some nice touches to make it unique, at least when compared to other coolers. DeepCool uses a dual-tower design with a top that is shielded with a black plastic cover to hide the top of the fin stack. The DeepCool logo can be found on the bottom edge, and the entire shield has a matte finish with a glossy grid array to make for a neat effect. The cover is easily removable if you so desire, which is good if you accidentally install the cooler the opposite way. Otherwise, the whole cooler is mostly black in color with some grey and teal accent parts on top of the silver aluminum fin stack. The fans are black with a blocky frame to maintain this angular design.
This is a dual-stack tower design, but the DeepCool AK620 has a similar height profile to other 120mm based coolers like the Noctua NH-U12S redux, which should make it compatible with most mid-tower ATX cases. The fins are hidden here, but there is an interesting design on the front with a grid like cut-out to make for a neat look. There are a total of 49 fins on each stack with four cut down fins at the bottom to ensure better RAM clearance. The spacing between each fin is approximately 2.0mm and they are all pretty evenly spaced between each other. From my calculations, the total surface area of the dual stack cooling fins is approximately 0.92 square meters, which is pretty good, but also not too surprising considering this is made up of two stacks. This surface area is notably more than coolers like the NH-U12S redux and the Noctua NH-U12A, but we will see how these compare later in our review. At a total mass of 1144g with both fans attached and 844g for just the heatsink, the DeepCool AK620 has quite a bit of heft to it. For some perspective, a typical AMD Wraith Prism stock cooler weighs 582g. Most of this weight is attributed to the material choices of the heatsink itself, as you will find out later.
As for its dimensions, the DeepCool AK620 is pretty typical with a height of around 160mm, a width of 129mm, and a depth of 138mm, with the two fans attached. You probably will not run into any issues with installing this cooler in most mid-tower ATX cases. The DeepCool AK620 is symmetrical and with its fans attached, it hovers over two of the closest memory slots. There is still quite a bit of clearance underneath with approximately 4.2cm of space between the bottom of the base and the bottom of the hovering fan, in its default position. You can readjust the fan to increase the clearance, but this will also increase the overall height of the cooler, so keep this in mind. Even so, I think these are all perfectly acceptable clearances for a dual-tower designed cooler.
From the base where the metal makes contact with the processor, six continuous U-shaped heatpipes lead away from the CPU contact and splits into the two stacks of fins. This effectively makes twelve heatpipes in total. The 6mm diameter heatpipes are supposed to efficiently lead the heat away from its source due to the low heat of vaporization, or phase change energy, of alcohol. The heatpipes are aligned in manner to spread out the heat in the array of radiating fins. The 0.92 square meters of surface area, combined with the two 120mm DeepCool fans, should be able to deliver very good heat dissipation performance, but we will see if this statement is true on the next page.
The two fans mounted on each fin stack of the DeepCool AK620 is mounted with metal wires that clip to the side of the stacks. This means you can swap out these fans if you so desire for any other 25mm thick 120mm fan. These clips work really well since they ensure the fan stays attached while also allowing flexibility in mounting height, if this is necessary. You will need to remove these fans during installation, but we will explore this later on.
As for the fans in question, we have two 120mm DeepCool FT120 fans. Internally, we have fluid dynamic bearings for a longer lifespan and generally quiet operation. These 120mm fans have a specified rotational speed of 500 to 1850 RPM with a maximum airflow rating 68.99 CFM and maximum air pressure of 2.19 mm H2O. The rated fan noise is around 28 dbA. These rated numbers are pretty typical for a radiator or heatsink mounted fan, as these sorts of fans require a sufficient amount of static pressure and airflow to get air through the fins. The rated lifespan of these fans is around 50,000 hours, which translates into around 5.7 years if operated 24/7. Otherwise, the fans are all black and have a very blocky frame design to match with the squared off look of the AK620. The corners have rubber padding to reduce vibrations between the fan and the heatsink it is mounted to.
The photo above shows the bottom of the DeepCool AK620 and how the heatpipes more clearly lead out of the base and into the fin array. The base is very flat, which should translate into the entire base pressing evenly on top of the processor. A quick inspection also reveals there are no abnormalities here, with no milling marks seen. This whole heatsink is composed of different materials. The base and heatpipes are composed of copper with a nickel plating on the outside. Copper is used because it has one of the best heat transfer abilities with a thermal conductivity of 401W/mK. Meanwhile, the fins are made up of aluminum as it is quite a bit lighter in comparison to copper. This reduction in weight will reduce stress on the motherboard, athough aluminum has a lower conductivity of 237W/mK, which is not as optimal for heat transfer, but the trade-off is understandable.
In terms of appearances, the copper base is concealed with an electroplated nickel. While nickel has a notably lower conductivity of 90.9W/mK, this layer is very thin and should not adversely affect the performance to a significant degree. Instead, nickel and nickel-base alloys are used here because of its properties in withstanding corrosive environments and high temperatures, which is especially beneficial for a heat dissipation device. The reason why nickel has these properties is because of its ductility and toughness all the way up to the melting point of 1455c, measured at non-standard pressure. Nickel's face-centered cube crystal structure is highly resistant to corrosion, so corroded material will not build up on the surface in the long run. As a result, the DeepCool AK620 will be less prone to losing its cooling performance over time as juxtaposed to a corroded copper surface.
At the base, all of the joints are soldered to the base, but the fins are pressed to the heatpipes. Pressed fins are pretty typical, but this may lead to degradation over time as contact between metals decreases due to thermal expansion and contraption. Overall, everything does seem to be well put together on the DeepCool AK620 with a solid choice of materials around the heatsink and fans.
Installation of the DeepCool AK620 is quite straightforward and imitates other competition's system in how it works. While this might be seen as copying, it is also one of the most seamless mounting experiences, which is great for the end user. With AMD systems, you will be using the stock motherboard backplate for mounting the two arms on, but if you are using an Intel system, you will need the included metal backplate. This comes with fixed bolts for installation of the entire unit. Once again, if you purchased the most recent LGA1700 socket motherboard, you will need separate mounting equipment, which can be obtained directly from DeepCool.
Once the backplate is secured, you can use two mounting bars to attach on the CPU side with plastic spacers to insulate metal from touching the rest of the motherboard. DeepCool again has separate bars for AMD and Intel motherboards, so do be aware of which arms you use. After using the right bars, you can tighten the thumb bolts on the bars and install the heatsink.
Before installing the heatsink, you should place thermal paste on your CPU. DeepCool has provided a small tube of paste to do so. Afterwards, with the fans removed from the fin stack, you can place the whole AK620 on top and screw the unit onto the mounting bars. With the L-shaped screwdriver, I was able to do this easily. Be sure to tighten these screws in an alternating fashion to evenly attach the heatsink to the motherboard. Finally, you can stick the two FT120 fans with wire clips to the heatsink. As I have pointed out before, the front fan hovers over my RAM, but it does not interfere as my kit is generally low profile.
1. Introduction, Packaging, Specifications
2. Physical Look - Hardware; Installation
3. Test Results