VANTEC 4-Port SuperSpeed USB 3.0 PCIe Host Card Model UGT-PC341 Type: PCI Express to USB Card External USB Ports: 3 x External USB 3.0 Ports (Backwards Compatible with USB 2.0 & 1.1) Internal USB Ports: 1 x Internal USB 3.0 Port Standard: USB 3.0 Data Transfer Rate: Maximum Transfer Rates Up to 5 Gbps w/USB 3.0 x0AMaximum Transfer Rates Up to 480 Mbps w/USB 2.0 Operating Systems Supported: Microsoft Windows XP, Vista & 7 (32/64bit) Specifications: Power: 4-Pin Molex (Includes SATA Power Converter) Dimensions: 4.72 x 3.19 x 0.75