Power supply unit power 500 watt max power 550 watt certificates 80 plus bronze noise emission 237 db pci express connectors 8 pin 2 serial ata connections 6 cable management non modular mains voltage 100 240 volt mains frequency 50 60 hz efficiency 20 87 efficiency 50 91 efficiency 100 87 cooling system active max fans 1 fan diameter 120 mm rpms 1 243 rpm power factor correction active special features energy star 60