Western Digital Gold. Hard drive capacity: 4000 GB, Hard drive interface: Serial ATA III, Hard drive speed: 7200 RPM. Power consumption (read): 9 W, Power consumption (write): 8.7 W, Power consumption (idle): 7 W. Width: 4" (101.6 mm), Height: 5.79" (147 mm), Depth: 1.03" (26.1 mm)