Cooler Master UCP 900W

Temperatures, Fan Speed, and Acoustics

The two heatsinks remain at reasonable temperatures throughout testing. We've seen much worse results with other power supplies topping out at up to 90°C, so the worst result of ~54°C on the secondary heatsink is quite good. It reaches this point at about an 80% load, and then the fan speed increases and temperatures remain static up to 110% load. This indicates that everything is working properly and there shouldn't be any problems with long-term use of the power supply, and even if it's running at closer to 100% load.

The fan spins at a relatively slow 860RPM up to a load of 300W, at which point it begins to spin faster. It's at 1100RPM at 80% load (720W), and it no longer qualifies as a quiet PSU. Beyond 80% load, fan speed increases rapidly up to the maximum 2000RPM, keeping things cool as we have seen in the temperature graph, but your ears might not be as happy....

If your goal is to have a quiet or near-silent power supply, you will want to keep this PSU under 500W of load. Once we pass 700W, noise levels increase rapidly from 20dB(A) up to a maximum 31dB(A). Given the relatively tame temperatures, Cooler Master certainly could have lowered fan speeds and noise levels more, as the heat sinks are usually in the 40-50°C range. However, we won't complain too much as it will be quite difficult for most users to come anywhere near 100% load (or even 80% load) on this power supply.