The Antec KÜHLER H2O 920 is very reminiscent of other ALC units with all the components of a custom water cooling unit integrated into a single maintenance-free enclosed system. The main difference to the previously reviewed Corsair H50 and CoolIT Eco is the size of the radiator but there are many other more subtle differences. Since the Corsair H50 is from the same family of coolers, albeit an older design, it’s easier to compare this Antec unit to it. Asetek have opted for a smaller sized pump and CPU block unit in this case, suggesting an improved more compact design. The KÜHLER H2O 920 uses two 120mm fans on the radiator for raw performance. Integrated to the radiator is the reservoir and the two hoses transport the pre-filled liquid to the CPU block that also integrates the pump.
The main advantage of such a unit is that everything is pre-assembled and designed to be leak proof, thanks mostly to the inability to dismantle the unit. All the components are tightly pre-assembled to reduce the risk of damaging the cooler and prevent leakages. Another advantage over air coolers is the fairly compact package the unit comes in. The radiator is the largest and heaviest component but due to being installed to the chassis instead of the motherboard, it is more secure. This leaves the CPU block and pump being the only components being installed to the motherboard, thereby not putting a lot of pressure. The question is whether the radiator has the same cooling capacity of larger air coolers.
The 120mm radiator
The radiator is 49.5mm thick and features 9 banks of aluminium fins. These fins are tightly spaced at 1.5mm and the width of each individual fin is 11.5mm. The fins follow a corrugated pattern to maximise surface area for better heat dissipation. The bands to which the fins are attached to transport water so that heat can dissipate across all the fins. Antec’s packaging meant that the fins remain undamaged during transit thus retaining a cleaner look.
Radiator fan spacing
To make sure that users don’t accidentally knock the fins and bend them out of shape, there is a gap left between the fins the four fan mounting holes. It also reduces the likelihood of puncturing the narrow linear bands through which the liquid flows through across the radiator. Another benefit is that the fan doesn’t sit as close to the fins and generate a higher pitched noise.
The reservoir is integrated into the radiator on the KÜHLER H2O 920 like all other ALC units. The two compartments are each connected to separate tubing so the liquid flows into one and out of the other once it flows through the entire radiator. The tubes are connected to barbs and tightly secured so users can’t pull them off and to prevent leakages. These barbs are designed to withstand high pressures and temperatures although they are not comparable to those used in custom water cooling loops. The fluid used in the system is de-ionised water with a propylene-glycol additive to prevent corrosion of the components.
The tubes are 33cm in length and have a rubberised feel. They are fairly tough but at the same time designed to be flexible. This is achieved by using a non-corrugated design as found on previous Asetek designs. In practise, the tube was quite flexible but the length made it restrictive went trying to install the block and bending the tube into shape. Thankfully the length of the tubing is perfectly distanced such that the radiator can be installed to the exhaust of a chassis.
The CPU block with integrated pump
On the other end of the tubes is the CPU block with the pump integrated into it. The pump operates at 3000RPM +/- 10%. It’s quite an achievement for Asetek to have designed a smaller pump, making the whole block 29mm in height compared to the tall cylindrical shape of the Corsair H50. The KÜHLER H2O 920 model name has been printed on top and more uniquely to the Antec is a translucent logo through which light is emitted from. Users can customise the colour of the LEDs using the bundled software to match their system.