Just tell them the board is dead. They HAVE to honor the warranty. You also have the recall on your side, too.

If they refuse to, contact the credit card company and do a charge back. You'll most likely wind up getting your money back and making some rude businessmen very, very unhappy...

(In some cases, you even get to keep the board, too).

BTW make sure you clear the cmos with the power plug unplugged.

And if the board has a backup BIOS, you may be able to switch the backup with the main bios, or if they are socketed, even remove the bios chips and swap them (but I don't know how you flash the backup bios on that board).