Information and communication technology improves the efficiency of economic activities and government by leaps and bounds, and networks are expected to continue to grow and gain functionality. In the modern age, the data sizes and traffic traveling over networks are rising. To accommodate this, the number of servers installed is rising day by day, and data maintenance is becoming ever more important. Thus, data centers are being built worldwide, but the amount of power consumed to accelerate their devices and keep them running 24 hours is extremely high and causes environmental problem. Also, running cost for power is becoming extremely high. Lately, engagement with environmental problems such as global warming is on the rise, with industrial organizations such as the Green IT Promotion Council and the Climate Savers Computing Initiative working to cut environmental loads; and so there is a need for power devices that save energy more (e.g. 80 PLUS gold).