Everything needed (monitor, peripherals, motherboard w/CPU and GPU, radiator, PSU and so forth) was placed in a sealed climate controlled box at 25 +/- 0.05 ºC. Each radiator was connected by Koolance QD3’s for easier changing of fans and radiator. The flowrate was held at 1 GPM constant. The CPU, an Intel i7 4770k at 4.6 GHz and 1.3 Vcore, was held at a constant load using a custom XTU profile and the GPU, an EVGA GTX 780 Ti Classified KPE under load from Unigine Heaven 4.0 at 1080p/extreme HD settings, was overclocked and overvolted such that the total system power draw was 550 W as measured by a power meter. A near constant heat load into the liquid loop helped achieve stable liquid loop temperatures (as measured by 3 separate in-line temperature sensors hooked up to the AQ6) pretty quickly. The tubing and fittings were insulated by a heater sleeve with the heat function not being utilized. Every single measurement was done twice to be sure. Any possible effects of running a fan outside of a static max speed was minimized as much as possible by using a comprehensive series of fans to cover a broad RPM range.
Results and discussion
Please note that lower is better here.
Here’s a condensed version of the results:
The PrimoChill EximoSX is an average performer at best, and a lot of this has to do with trying to achieve something at all fan speeds with the lower thickness, fin density and louvering rather than trying to optimize for a specific application- higher performance or low noise, for example. It reminds me a lot of the Alphacool NexXxos ST30, and here too we see two upwards trend with first the thickness coming into play and then the fin density and fin louvers. Ultimately, it is a decent performer but I would not recommend it from a pure thermal performance point of view as there are better options out there. Oh, the astute observer may note a 9th radiator here which was reviewed elsewhere but included here either way.