I got myself the map, because I suffice 2 ports and the P / L ratio is pretty good. Instead of 25MB / s, I can now move back and forth with 90MB / s data between external and internal drives. Under Windows 8.1 64-bit card has been started immediately without their own driver installation. My external hard drive and other USB devices are recognized anstandlos and function properly. Anyone who wants to upgrade his PC low on USB 3.0 can access them easily here.