Yeah, the BIOS is completely stored in hardware and is flashed onto a chip when the motherboard is manufactured. The only time that changes is if you run a BIOS update program that flashes the chip with a new BIOS image.

That said, it seems strange that an X-X board would be running an X-Deluxe BIOS...
You may want to check the Asus KB and support forum to see if anyone else has had similar BIOS version issues:
http://support.asus.com/default.aspx