I think the only option is to have the BIOS chip desoldered/removed, inserted into a chip programmer, and reflashed. This is a failsafe procedure, but is not for inexperienced people. You can wipe any failed code from a chip, and reflash the banks, one by one.
Once a BIOS flash goes wrong for whatever reason, the machine cannot start, the POST does not even begin to execute, or will stall at any point, depending on where the corruption in the code is. The optical drive and hard drive will make some sort of noise, as they will anyway on power up, their internal firmware runs its own checks, mechanically and software wise. BIOS flash errors occur, but it is usually due to errors in downloading from the Internet, transferring from media, etc that causes it. That's why I never suggest BIOS flashes from floppies
, they are total junk. I always try to make a bootable CD from them, if possible, and use a fresh disk if I do, performing write and read back tests.
Windows based utilities are much better, and more and more manufacturers are starting to use them. They perform their own checks to make sure the BIOS is actually working, but do not offer warranties, including refunds or technical service for failed flashes.