MSI MS-9804 User Manual page 48

MS-9804 Mainboard
USB Configuration
USB Legacy Support
Set to [Enabled] if your need to use any USB device in the operating system
that does not support or have any USB driver installed, such as DOS and
SCO Unix. Set to [Disabled] only if you want to use any USB device other
than the USB mouse.
USB 2.0 controller mode
Use this field to select the USB 2.0 mode.
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