6 – Performing the BIOS flash

Now that we’re thoroughly prepared, it’s time for the actual procedure.

Insert the boot floppy you prepared and restart your computer. You will end up at a DOS prompt for the floppy drive A:\.

At the A:\ prompt, type the command line you prepared earlier to run the flash utility and program the BIOS.

Since you already provided all the details via switches, the flash program should run without interruption. First it backs up the current BIOS to a file on the floppy disk.

Then it programs the BIOS chip with the new BIOS.


The process is very quick and uneventful. It took less than a minute to flash this BIOS, no user input required, and it went smoothly.

Now it is time to reboot. Watching the screen after the reboot we can now see the updated BIOS version TH in the BIOS identifier string at the bottom.

Immediately go into the BIOS after the reboot, do not let the operating system boot yet. In the BIOS, go through each screen and configure it with the proper settings that you documented earlier. Double-check all the settings for accuracy. Misconfiguring the BIOS can lead to system instability or hardware failure, so be thorough.

Once the BIOS is configured properly, reboot one more time, and this time let the operating system boot as usual. Everything should come up normally. It is possible that Windows might announce that it found new hardware and starts installing drivers. That’s ok, it is a result of the Plug’n’Play data being cleared during the BIOS flash. Since all your hardware was already installed before the flash and Windows has all the drivers, it should automatically install them without incident. You might be prompted for one last reboot after this is done.

You’ve successfully flashed your BIOS

As you can see, flashing the BIOS is not as scary or mysterious as it may sound. It is a process consisting of a simple series of logical steps. Performing these steps with care, patience, and preparation will minimize the risks of the procedure.

Page 1: Basics of CMOS/BIOS flashing

Page 2: BIOS flashing utilities (and precautions)

This page: Performing the CMOS flash

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