You'll be fine jamjar.
DOS BIOS INSTALLATION INSTRUCTIONS
1. Copy the new BIOS (691N1P24.BIN), the DOS-based BIOS Update Utility (NVFLSHSC.EXE), and the flash.bat files to a floppy disc or bootable USB flash drive.
2. Using a bootable floppy or bootable USB flash drive, boot to DOS.
3. Type "flash" at the DOS prompt to begin the BIOS update. Alternatively, you can type the command line "NVFLSHSC.EXE 691N1P24.BIN".
4. Once the flash process is complete, remove the floppy/USB drive and reboot the system.
5. IMPORTANT: Upon reboot, press <Delete> to enter the BIOS, and select "Load Optimized Defaults".
Get any problems add me to msn and i'll happly guide you through the process.