Cooler Comparison Testing
Cooler Testing Methodology
To best gage the quality of the system coolers under review, system CPU temperature and cooling system audio measurements were taken with the CPU idle and under load. To replicate CPU idle conditions, the system was rebooted and allowed to sit idle for 10 minutes. To replicate a stress system load, AIDA64 System Stability Test was used in conjunction with EVGA OC Scanner X for 30 minutes per run. After each run, the system was shut down and allowed to rest for 10 minutes to cool down. Then the CPU cooler was removed, cleaned, and remounted to the CPU with fresh thermal paste applied. This procedure was repeated a total of six times for each cooler – three times each for the stock and overclocking speed runs on the X99-based system.
Temperature measurements were taken directly from the CPU thermistors using CoreTemp v1.61. Because of the volatile nature of the Haswell-E thermistor readings, the system temperatures were measured as follows. For idle temperatures, the highest recorded value was used for the run. For load temperatures, a series of three values were notated: the average (high and low) across all cores, the average (high and low) across the single highest core, and the high temperature.
To measure the performance of the water cooler kits tested, performance testing was done with the blocks in their default configuration only – with its logo readable with the board in a vertical orientation.
Note that the temperature values are reported as deltas rather than absolute temperatures with the delta value reported calculated as CPU temperature – ambient temperature. For all tests, room ambient temperature was maintained between 23-27C.
Intel X99-based Haswell-E System Testing
CPU Stock Speed Testing
The CPU stock speed testing was conducted with the BIOS defaults set for the CPU and Turbo Mode disabled, equating to a 3.0GHz CPU speed, 2133MHz memory speed, 3.0GHz ring bus speed, and 100MHz base clock. The Intel Speedstep functionality remained enabled for the duration of the testing to get realistic CPU idle performance conditions.
With the Haswell-E processor at stock speeds, there is little performance difference between the different water cooling kits let alone between the NexXxos XP3 Light and the Eisblock XPX blocks. Adding additional fans to the NexXxos kit also seemed to have little impact on either block's performance.
CPU Overclocked Speed Testing – Maximum water-cooled speed
The CPU overclocked speed testing was conducted with known stable settings from a previous board review with Turbo Mode disabled, equating to a 4.50GHz CPU speed, 2666MHz memory speed, 4.0GHz ring bus speed, and 100MHz base clock. The Intel Speedstep functionality remained enabled for the duration of the testing to get realistic CPU idle performance conditions.
Board voltage settings were configured as follows:
- CPU Core Voltage – 1.35
- DRAM Voltage – 1.23
- All other settings set to Auto or stock settings
In its default state with three fans and the NexXxos XP3 Light block, the system would not stabilize for more than 1 out of 4 runs. Similar behavior was seen using the Eisblock XPX block with the kit's default configuration. When an additional three fans were added to the NexXxos kit, the system's performance stabilized when using the Eisblock XPX block but remained unstable with the NexXxos XP3 Light block. Performance using the Eisblock XPX block dropped a mere 3C when paired with the NexXxos kit instead of the XSPX Photon kit. However, the stability issues encountered with the NexXxos XP3 Light block when paired with the NexXxos kit remains puzzling. The hypothesis, which the test data seems to support, for the NexXxos XP3 Light block's performance challenges is that the NexXxos kit's pump outbound flow path, radiator thickness, and fan speeds all collude to impact the performance of the block negatively. The Eisblock XPX CPU block is not as effected by the kit because it is a better performing block.
When running at full speed, the NexXxos kit remains barely audible when using either the 3-fan or the 6-fan configuration with the fans running at full speed. This is mostly because of the lower speed ratings of the included fans – 1300RPM vs the 1600-2000 RPM of typical 120mm case fans.