When paired with the stock speed Haswell-E processor, the Alphacool NexXxos Cool Answer 360 D5/UT water cooling kit performs on par with other tested kits. The NexXxos kit's performance begins to suffer under overclocked conditions. The kit could not keep the system stable until an additional three fans were added to the radiator using the Eisblock XPX CPU block only. The system would not stabilize at all with the NexXxos XP3 Light CPU block.
As of April 26, the Alphacool NexXxos Cool Answer 360 D5/UT water cooling kit was available at Amazon.com for $352.95 with Prime shipping, at Newegg.com for $313.94, and at PerformancePCs.com for $314.95.
Alphacool NexXxos Cool Answer 360 D5/UT Water Cooling Kit
Courtesy of Alphacool
The Alphacool NexXxos Cool Answer 360 D5/UT kit is a nice looking kit. Its clear and black aesthetic is sure to blend well in most builds. Further, the build quality of the included components is superb with everything easily fitting together perfectly. The Achilles Heel with this kit seems to be the performance of the components included with the kit itself. In its default state, we could not get our Haswell-E based test system to stabilize at known stable overclocked speeds. Kit performance improved by replacing the stock CPU water block with the Eisblock XPX CPU block and increasing airflow through the radiator by adding three additional fans to the radiator. However, the kit's stock block, the NexXxos XP3 Light CPU block, would not keep the system stable even with the additional fans on the radiator.
The XP3 Light CPU block's performance with the kit was puzzling, especially given its decent performance under stock and overclocked conditions when paired with the XSPC Photon kit. There are several differences between the two kits including tube diameter (ID / OD), pump outbound flow path, and fan speed while both kits share similar thicker 60mm radiators. The Alphacool NexXxos Cool Answer 360 D5/UT kit uses slower fans (1200RPM vs 1650RPM) and thinner tubing (3/8" ID vs 7/16" ID). Additionally, the outbound flow path for the Alphacool kit goes through a hard 90 degree bend on its path through the reservoir channels to the outlet port, compared with the straight-through to the outlet on the XSPC reservoir. This complex outlet path on the Alphacool reservoir can act to erode the coolant flow-rate. The differences between the two kits seemed to collude to create coolant flow and heat dissipation issues for the Alphacool kit. The lower flowrate as a result of the pumps outboard coolant path causes coolant to flow more slowly through the CPU block, decreasing the block's heat dissipation potential. At the same time, the lower flow rate increases the heat dissipation potential of the radiator, since the coolant spends more time flowing through the radiator. The thickness of the radiator works against the coolant's flow rate, causing a decrease in the rate of coolant exiting the radiator. The thickness of the radiator becomes a challenge for air flow through the radiator's cooling fins, requiring fans with a greater static pressure to effectively push air though the radiator to optimally disperse the coolant's heat. Unfortunately, the three fans included with the kit are not up to the task, leading to an increase in coolant temperature over time, and requiring the six fan configuration to provide enough air flow and static pressure to effectively cool the coolant. Alphacool attempts to mitigate the flow rate issues using smaller diameter tubing, but its does little to compensate for the other issues with the kit. The Alphacool kit would perform much better with a stronger pump and either stronger fans or more fans.
- Quality of user manual
- Performance under stock conditions
- Kit aesthetics
- Sleek flat black and black chromed appearance
- Build and machining quality of included components
- Easy to use CPU mounting mechanism
- No enough coolant included to fill loop
- System instability with included block using overclocked CPU
- Complex outboard flow path between pump outlet and reservoir outlet port
- Inclusion of low noise fans in kit
- Need of six fans to stabilize system performance under overclocked conditions