The WD Green 4TB Internal Hard Drive is an integral component when upgrading, repairing or building a PC. With WD GreenPower Technology, it yields lower operating temperatures for increased reliability and low acoustics suitable for ultra-quiet PCs and external drives. The SATA connection transfers data at speeds of up to 6Gbps, allowing files to be saved and retrieved quickly. The 4TB capacity gives the WD desktop hard drive a large amount of space for holding important data and software. It has the room for as many as 800,000 photos, 1,000,000 songs or over 300 hours of HD video.