The cooling of the OCZ ZT 550W unit is taken care of by a 140mm fan which is commonly found inside high quality power supplies. The fan is made by Yate Loon, a Taiwanese electronics manufacturer, and it is a ball bearing fan with a maximum rotational speed of 2800RPM.
The OEM behind the ZT 550W unit is Great Wall, a designer we first encountered when testing very high output power supplies. The same OEM is responsible for the premium class ZX series units.
The filtering stage of the ZT 550W unit is good, although not remarkable. It starts at the back of the A/C receptacle and continues on the PCB. It totally consists of four Y-type capacitors, two X-type capacitors and two ferrite coils. Strangely, the power supply does not have a surge arresting MOV, an omission which is very unlike OCZ.
The primary capacitor of the power supply sits next to an enclosed PFC choke and is supplied by Teapo and is rated at 420V/390μF at 105°C. Nippon Chemi-Con supplies the secondary side capacitors.
The heatsinks of the ZT 550W power supply are dense and of average size but should prove to be more than adequate considering the product’s efficiency and power output.