SuperSpeed USB 20Gbps / internal USB-C Key-A 3.2 Gen 2x2 PCIe expansion card. Includes optional low profile slot cover for supporting low profile cases. Remark : * User should confirm which OS version support xHCI driver natively. * If your operating system is incompatible with the expansion cards developed by SilverStone, such that your device can not be detected or recognized, please update your motherboard’s driver or BIOS to the latest version. You may also try executing compatible mode in your operating system and select previous versions of operation system to install driver required by the expansion cards. * if the transfer speed cannot reach the 20Gbps, please check the below items 1.PCIe version of motherboard 2.Key-A cable lanes, 20Gbps transfer speed must have 2 lanes cable 3.Key-A cable quality and cable length (internal + external cable)