Perhaps the usb keyboard setting is disabled by default and it's no longer detecting your usb keyboard since you cleared CMOS.
Get a PS/2 keyboard or a USB to PS/2 adapter. You can find an old keyboard at a thrift store for less than $5 if you either don't have one, can't borrow one, and don't want to pay for a new one or an adapter.
This specific motherboard does not have a PS/2 port. And where do i get a USB to PS/2 adapter. It seems like the USB ports are no good or something. If USB Legacy is turned off then would all usb ports some how deactivate? The front ports do not work either.