Iomega 500GB StorCenter Pro 250d Series + REV 70GB Disk. Total storage capacity: 500 GB, Hard drive capacity: 250 GB, Hard drive rotational speed: 7200 RPM. Memory type: DDR2 RAM, Internal memory: 256 MB. Supported network protocols: TCP/IP, AppleTalk, IPX, NetBEUI. Bundled software: Iomega NAS Discovery Software EMC Retrospect Express (5 client), Operating system installed: Windows Storage Server 2003 R2. Power requirements: 115-230V; 50/60Hz, Power supply: 270 W