Be Quiet Dark Power Pro P9 550W PSU review
Be Quiet entrusted the cooling of their Dark Power Pro 550W unit to one of their own SilentWings USC 120mm fans. It is a fluid dynamic bearing fan with a patented high airflow design. According to the unit’s specifications, this fan has a maximum speed of only 1010RPM.
The layout of the Dark Power Pro 550W unit is unlike any other power supply we have ever seen. Fortron Source (FSP) is the manufacturer of this power supply but it appears that it is a custom design from Be Quiet engineers, meaning that no other units are likely to be sharing the same design.
The filtering stage is acceptable, with four Y-type capacitors, two X-type capacitors, two ferrite coils and a surge suppressing MOV.
The primary capacitor is made by OST, a company we rarely see in high performance power supplies. The capacitor is rated 450V/470μF at 85C. All of the secondary side’s capacitors are made by OST as well.
The heatsinks of the power supply feel adequate considering the Dark Power Pro’s efficiency and power output. The bridge rectifier can be seen on its own dedicated, although basic heatsink.
To maximize this product’s efficiency, Be Quiet used the best technologies currently available. The Dark Power Pro 550W unit features a LLC resonance circuit with a downstream DC to DC converter. It also has a user-selectable OCP design which allows the user to choose better either 4 smaller 12V lines or a single large 12V line.