Zalman GigaMax 550W PSU 80 PLUS Bronze Rated ATX Power Supply Unit Superior Efficiency & Energy Savings80PLUS BRONZE 230V EU guarantees 85%, 88%, 85% efficiency with 20%, 50%, and 100% load rated, significantly reducing overall system power consumption. The higher efficiency of the PSU means that there is less leakage of the current, which means less heat, high frequency noise, and fan noise. It is powerful, quiet, and durable.High Quality Performance PartsDesigned for durable and reliable system operation, it supplies power to the PC while reducing unnecessary power consumption by using high performance parts that are very durable and reliable.Quiet and Long Lifespan Cooling TechnologyFDB (Fluid Dynamic Bearing) has benefits of low noise and long lifespan. It discharges internal heat quickly and provides sufficient cooling at a low RPM to maximise stable, safe power supply.System Standby Power at 0.5W or LessZalman\'s power supply has such remarkable energy efficiency, that during standby the power supply can be kept at under 0.5W to avoid any unnecessary power consumption. The power supply has aquired ErP Lot 6 which passed European Energy Saving standby for environmental friendly and energy efficient experience for users.