Silverstone PCI-E to USB 3.0 Add-On Card Model SST-EC04-P Type: PCI Express to USB Card External USB Ports: 2x USB Ports Internal Ports: 19 pin Dual Port Standard: USB 3.0 Data Transfer Rate: Up to 5.0 Gbps Operating Systems Supported: Windows XP, Vista, 7 (32bit / 64bit) Specifications: Power requirement: 5V DC via peripheral 4pin power connector Form factor: Low profile single lane (x1) PCI Express 2.0 USB 3.0 controller: NEC uPD720201 USB bus power output: 5V DC / unlimited current Transmitting Speed: USB 3.0 (5Gbit/s), USB 2.0 (480Mbit/s), USB 1.1 (12Mbit/s)