I was trying to delete a recovery partition on a Unisurf Windows Tablet for more space however that turned out to contain the boot loader. I was able to boot from a USB drive to reinstall windows but it wouldn't detect any of my keyboards. I changed something to do with the XHCI in the BIOS however this completely disabled the USB port. I need to reset the BIOS but I don't know how. I opened it up but couldn't find anything that looked like a CMOS battery.
How can I reset the BIOS?