Features:Supports PCI Express2.0 X1 Lane, can transferring up to 5Gbps MAX.Supports USB 3.0 specification typeA Connector X 4ports.Backward compatible with USB 1.1/USB 2.0.Supports the following speed data rate: Low-speed(1.5Mbps)/Full-speed(12Mbps)/High-speed(480Mbps)/Super-speed(5Gbps).Supports External power plug in order to supplying power for each USB3.0.Up to 900mA MAX/port.System Requirements:PC with 512MB of RAM and 1.0GHz or faster processor.One available PCI Express 1.x/4.x/16.x slotSystem Support: Windows XP / Vista / Windows7 (32/64 bit)/Windows8 (32/64 bit). Note:To achieve the maximum throughput, the PCI-Express slot must be version 2.0 or higher. Performance per port may decrease if multiple ports are transferring data simultaneously due to limited throughput of the PCI-Express slot.To meet USB 3.0 transfer speed, high quality USB 3.0 cables and devices are required.Supports both 32-bit & 64-bit OSes.Make sure the power is well connected; otherwise you will see a "Power Surge on Hub Port" message error and no 5V bus power in USB ports.Specifications:Certifications: CE, FCC, RoHSItem size: 12 * 6.5cm / 4.7 * 2.6inItem weight: 45g / 1.6ozPackage size: 15 * 13 * 3cm / 5.9 * 5.1 * 1.2inPackage weight: 98g / 3.5oz