PCI USB Card 4 Ports Ports: 4 External Ports 1 Internal Port (Shared Port) Plug and Play Installation for Windows 7, Vista and XP USB 2.0 EHCI and USB 1.1 OHCI Compliant Backward Compatible with USB 1.1 Devices Transfer Rate: Up to 480Mbps Connects up to 127 USB Devices Simultaneously Over Current Protection (500mA Each Port)