Results: Silent Pro Platinum 550 W
Efficiency According to the 80 PLUS Specification
Efficiency by Output Power
Cooler Master's Silent Pro Platinum 550 W not only holds its own in our lab tests, but its efficiency even tops the Kingwin Lazer, which just broke Antec's efficiency record two pages ago. At both 20 and 50 percent load, it takes a one-percent lead over the last power supply we benchmarked, achieving 92 and 93 percent efficiency, respectively.
The trend continues at very light loads. No other power supply in this round-up is able to achieve 81 percent efficiency at 25 W. The Cooler Master supply coasts through the other metrics as well, including the tricky ripple and noise test. While the picture on the scope shows slightly larger ripples than Kingwin's exemplary PSU, the Cooler Master product easily complies with the requirements.
A Closer Look at the PCB
The main PCB, colored black, is smaller than the floor area of the enclosure. There is an auxiliary board mounted to a side wall, and massive cooling fins dominate the interior.
When we examined the input filter, along with the primary and secondary side circuits, we couldn’t find any flaws or evidence of cut corners. Cooler Master sources the most important components from suppliers in Japan, using premium parts in a modern circuit topology. The soldering quality is very good here as well (almost perfect, in fact). Not surprisingly, the Silent Pro Platinum 550 W sports a 135 mm fan made by none other than Cooler Master itself.