I agree with what you have written. Even though I use my old trusty floppy to flash my BIOS, if and when I get round to doing it and not just because there is a new version, it does seem that many motherboard manufacturers package a Windows version of their BIOS flashing tools often on the CD that comes with the board.
Then when you use it you find that people, for all the right reasons, inform you that you shouldn't have used it all along....!!!!
To the OP....
If clearing the CMOS / removing the Power and battery from the board for a period of time and using the minimum hardware attached doesn't resolve it then you could either return the board for a replacement or use a BIOS reprogramming service like....
http://www.motherboard-biosflash.co.uk/
...providing it is a socketed type of BIOS chip. I have used them before with success. On another occasion I hot-flashed my DFI board with my friends BIOS chips that I borrowed
With luck someone else might post with a useful suggestion that would get you up and going, best of luck