WD Caviar Green SATA hard drives reduce power consumption by up to 40 percent and offer best-in-class acoustics and operating temperature. Based on WD's exclusive GreenPower technology, these drives are designed to deliver power savings as the primary attribute. As hard drive capacities increase, the power required to run those drives increases as well. WD Caviar Green drives make it possible for energy-conscious customers to build systems with higher capacities and the right balance of system performance, ensured reliability, and energy conservation. They are ideal for PCs, external storage and other devices that require lower power consumption and cool, quiet operation.