Lion power supply- is a better than fan less power supply. The Lion is designed for users who care about both the noise and power output. A stand-by fan installed inside the Lion power supply which will kick into gear only when the system executing a load over 250W (like playing 3D games- graphic capture or heave graphic drawing). The Lion remained completely quite for light loading operation like word processing or Internet browsing. The exclusive silent operation definitely meet user requirement.FeaturesPower supply technology with user convenience in mindE Power Thunder series redefine a modem PC power supplyIt's not only a power supply for PCCharger for USB devicesSATA power source for external SATA hard drivesWe call it a 3 in 1 power supplyBlack caseLow ripple and noise100% Hi-Pot testedShort circuit protection on all outputsATX12V 100 - 120 V / 200 - 240 V 50/60 Hz +3.3V at 24A-+5V at 24A-+12V1 at 20A-+12V2 at 20A- -12V at 0.8A-+5VSB at 3.0ASpecificationsDimensions: 3.4- H x 5.9- W x 6.3' LWeight : 7 lbs