Chapter 3 – AMI BIOS Setup25Network Appliance FWS-22603.4.3 Advanced: USB ConfigurationOptions summary:XHCI Mode Enabled Optimal Default, Failsafe DefaultDisabledMode of operation of xHCI controllerLegacy USB Support Enabled Optimal Default, Failsafe DefaultDisabledAutoEnables BIOS Support for Legacy USB Support. When enabled, USB can be functionalin legacy environment like DOS.AUTO option disables legacy support if no USB devices are connected