Thermal Performance

For CPU water block thermal performance, I used my Core i7-5960X on the Asus Rampage V Extreme motherboard with the CPU overclocked to 4.4 GHz at 1.3 Vcore and paired it with 4x4 GB Corsair Dominator Platinum DDR4 RAM at 2666 MHz (CAS16-16-16-18). A Swiftech MCP35x2 pump, an Aquaero 6 XT controller, and a Black Ice Nemesis GTX 480 radiator with Noiseblocker NB-eLoop B12-3 fans completed the loop. The GPU used was not placed in the loop to make the only source of heat the CPU and, thus, the CPU block itself. Average flow rate was set to 1 GPM and calibrated in-line temperature sensors were used to measure the coolant's temperature.

Everything required was placed inside a hotbox, and the ambient temperature was set to 25 °C. Gelid GC-Extreme was used as the thermal paste of choice and cure time was taken into consideration. Three separate mounts/runs were done for statistical accuracy and to remove the chance of any mounting-related anomalies. For each run, a 90 minute Intel XTU stability test was performed. XTU is a stability test from HWBot that uses a custom preset of Prime 95 (no AVR), which ensured the load is uniform on each run. CPU core temperatures were measured using Aida64, and the average core temperature was recorded at the end of each run. A delta T of CPU core and loop temperature was thus calculated for each run, with an average delta T that was then obtained across all three runs. This way, the cooling solution is taken out of the picture. The effect of block orientation was also tested, and the best orientation was used for these runs, with the result shown below.


Color me surprised now! The arguably brute-force approach used in the cooling engine worked really well here, especially compared to the older Apogee XL. A lot of thought went into the design of the cooling here with the Apogee SKF - be it the large microfin area, higher-than-average fin array height coupled with the thinner-than-average cold plate thickness and, of course, the ultra-thin microfins which make for a much higher surface area of heat transfer relative to not only the Apogee XL, but other blocks from competitors. As it is, the Apogee SKF provides a much-needed improvement to the Swiftech lineup when it comes to pure performance, even if it comes down to a couple °C in the end.