The 500W QFan Toughpower Power Supply has an extremely quiet 140mm ball-bearing fan which decreases the noise level by 17%. It has a stable continuous output at 50°C operating environment and the 4 independent and dedicated +12V rails (12V1, 12V2, 12V3,12V4) provide stable and superior performance for PC system (combined loading of 36A). This power supply complies with ATX 12V 2.2 & EPS 12V 2.91 version and supports Dual Core CPU, Quad Core CPU, and Nvidia SLI and ATI Crossfire Multi-Core GPU technologies. The 500W QFan Power Supply comes with modularised cable management to eliminate clutter and improve airflow inside the case. The independent voltage circuit offers unflappable current delivery under heavy load and the strict voltage regulation (±3%) provides steady voltage for the system. This power supply has Active Power Factor Correction (PF>0.99) and high efficiency (up to 85%), it has Over Current, Over Voltage, and Short Circuit protections and Safet/EMI Approvals (CE, CB, TUV, FCC, UL, CUL, and BMSI certified). The QFan power supply uses japanese made capacitors which promise the best reliability and has green power design that meets energy star, blue angel requirements.