This SC-SA0G12-S1 Hard Drive Duplicator works as a standalone duplicator, no PC connection needed. Supports both eSATA and Hi-Speed USB (USB 2.0) interfaces, built-in silent cooling fan effectively extends hard disk drive life. Supports hard disk drive capacity up to 3TB hard disk capacity. Note: Windows 2000, XP (32-bit), Server 2003 (32-bit) can't support more than 2TB capacity. This is an OS limitation.