I got my hand on a 2005 computer which needed some fresh OS and a bios upgrade. The PC didn't have a working floppy drive but could fortunately boot on USB (which is not a given on older computers).
The trick was to get a USB stick with a bootable FreeDos on it. It was quite easy!
- Use gparted to create a single FAT16 formatted partition on the flash drive.
- Use unetbootin to install a bootable FreeDOS onto the flash drive.
- Run unetbootin and
- Select the distribution FreeDOS.
- Select your USB flash drive
- Click OK. This will download FreeDOS to create a DOS bootable flash drive.
- Copy your motherboard's BIOS update and flashing utility files into the root of flash drive.
- These files will be located in the B: drive after booting into FreeDOS.