SILVERSTONE SX500-LG 500W SFX-L 80 PLUS GOLD Certified Full Modular Active PFC Power Supply, Silent running 120mm fan with 18dBA minimum (SX500-LG V2.0) Fans: Silent running 120mm fan with 18dBA minimum (SX500-LG V2.0) Main Connector: 20+4Pin +12V Rails: Single PCI-Express Connector: 2 x 6+2-Pin SATA Power Connector: 3 Efficiency: 87%~90%(20% to 100% loading) Over Voltage Protection: Yes Overload Protection: Yes