Western Digital Caviar Green WD6400AACS 640GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive

The Western Digital Caviar Green 640GB Hard Drive uses less power and support quieter, cooler-running desktop PCs. Its breakthrough 16 MB cache makes this hard drive suitable for high-performance home and business computing, as it can handle high-end data-intensive and multimedia applications.