Hotflash; basically, remove the existing ROM from a working system and put your dead one in it.
With the power on. You should find some guidelines somewhere, but what I do is;
1. observe electrostatic safety guidelines to prevent static damage to your PC. Basically keep touching the metalwork and avoid touching the pins.
2. Locate working machine with similar size flash ROM.
3. Ensure jumpers are set to correct flash voltage, CMOS and jumpers are set to allow flash if necessary.
4. If "BIOS shadowing" is an option make sure it's enabled.
4. With power off, remove the BIOS ROM from the working machine. Ease it out slowly and carefully and avoid tilting the ROM as you lift it or you'll bend the pins.. Replace it lightly in the socket so you can lift it out with your fingernails or a piece of plastic, but make sure it's making contact.
5. Boot the machine with your BIOS image and Uniflash or similar.
6. Carefully but quickly remove the BIOS ROM from the socket. Don't use anything metallic to do this.
7. Carefully but quickly insert your target BIOS ROM in the socket (the right way round, of course !).
8. Flash. If there are errors you might like to check the chip is in the socket correctly.
9. Turn machine off and replace original BIOS ROM.
There are some options which involve building a little rig so you can have both ROMs in and switch from one to the other, but I haven't felt the need. Bear in mind it's easy to bend those legs so you need a firm but light touch.