OCZ Vertex 4 SATA III 2.5" SSD. Solid-state drive capacity: 256 GB, Size: 63.5 mm (2.5 "), Solid-state drive interfaces: Serial ATA III. Read speed: 560 MB/s, Write speed: 510 MB/s, Random write (4KB): 85000 IOPS. Security algorithms supported: 256-bit AES. Power consumption (standby): 1.3 W, Power consumption (read): 2.5 W, Power consumption (write): 2.5 W. Mean time between failures (MTBF): 2000000 h