The Thermaltake Toughpower 1000W W0155RU is a high-end power supply unit ideal for advanced users who demand greater cooling and higher power. The Active Power Factor Corrector (Active PFC) helps deliver a stable 1000 Watts of continuous output with up to 87% efficiency. Four independent and dedicated +12V rails (12V1, 12V2, 12V3, 12V4) enhance power distribution and provide superior performance for your PC. The Toughpower W0155RU is compatible with dual core CPU, quad core CPU, NVIDIA SLI, Quad SLI and ATI CrossFire technologies, with three 6-pin and three 8-pin (downward compatible with 6-pin PCI-E connectors) PCI-E connectors that allow connectivity to multiple graphic cards. The 14 cm ball-bearing fan reduces hot spots, and offers excellent and quiet cooling. In addition, the Toughpower W0155RU uses industrial grade components with Independent Voltage Circuits for stable, reliable output and protection against potential voltage surges. Reliability comes with a MTBF of more than 120,000 hours, and Fans: 1 x 140mm fan Main Connector: 20+4Pin +12V Rails: 4 PCI-Express Connector: 3 x 6-Pin, 3 x 8-Pin Power Good Signal: 100-500ms Hold-up Time: 16ms min. Efficiency: up to 87% Over Voltage Protection: Yes