Testing Results & Conclusion
We utilize data collected from previous review tests to provide standardized comparisons among CPU cooler hardware. Our AMD Threadripper 1900X clocked at 4.1 Ghz and 1.40 vCore running Prime95 v27.9 provides thermal load for our TR4 cooler benchmarks. Given that we've only tested a few coolers to use (thus far) for comparison on our Threadripper platform, the Cooler Master MA621P will face off against a pair of large, 360 AIO coolers in the Enermax LIQTECH TR4 OC and the NXZT Kraken X72.
An impressive initial result sees the MasterAir MA621P nipping at the heels of the large AIO coolers on overall thermal load temperatures. Motherboard power delivery and nearby hardware also sees benefits from the dual fan cooler.
Large heatpipe CPU coolers are cooled predominately by fans with slower rotational speed. Interestingly enough, while all coolers in our comparison each utilizes 120mm spinners, the MA621P still leans toward the ‘large cooler fan speed’ precedent.
Since the MasterAir MA621P has the fewest fans (2) and the lowest rotational speeds (1800 RPM at 100% PWM), it stands to reason that it also registers the lowest noise levels of the bunch.
Evaluating thermal performance and noise levels, acoustic efficiency of the MasterAir MA621P sees a well-balanced placing between full- and half-fan speeds when compared to the big AIO coolers.
Large AIO coolers traditionally carry a hefty price tag, which favors the more moderately priced Cooler Master MasterAir MA621P in our comparisons. Averaging a retail price of $68 at the time of this writing, the MA621P offers solid cooling performance at a comparable discount. Pricing on the MA621P has occasionally been seen even lower, which should entice Threadripper enthusiasts a bit more.
Thermal imaging from the FLIR One Pro shows a marked difference around the cooler’s heatpipes and center-mounted fan at 50% fan speed, as expected. Residual heat soak is readily visible through the plastic top fascia caps and areas immediately surrounding the cooling tower at these slower fan rpms. These issues can be easily remedied by defining a well-balanced PWM fan curve that takes advantage of the MA621P’s nearly silent fans.
The Cooler Master MasterAir MA621P offers great cooling performance, striking design, RGB lighting capability and low noise levels in a remarkably budget-friendly cooler. The MA621P handles the 8-core 1900X very well, even while overclocked, but might lag further behind the large AIO coolers on the 12-core 1920X and 16-core 1950X, especially when highly overclocked. Regardless, pricing makes the big Cooler Master look just that much more enticing.
The MasterAir MA621P, like its sibling the MA620P, appears to signal Cooler Master's intent on providing large heatpipe coolers that are a bit more monolithic, while still progressive in design. The plastic fascia caps are a good indicator of clear intent to create a stunning, visual statement inside any AMD Threadripper build, while bringing along the necessary cooling potential for performance PCs.
Just remember that installation can be a pain--particularly in cramped cases and/or if you don't remove most of your components first. This certainly ins't out of the ordinary for big air coolers, but it's worth remembering--particularly if you aren't an experienced builder with lots of patience.
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