There are very few scenarios where you need to flash firmware from a different model, nor do I recommend you do it, as 95% of the time it will result in a brick. Today, however, I needed to as part of another project I’m working on (had to hotflash a BIOS chip from a different motherboard). It was quite tricky to get it to work, but for anyone else getting a “ROM ID doesn’t match” or similar error and you KNOW FOR CERTAIN that you have the correct ROM (or you are also trying to hotflash a different board’s BIOS chip), read on.
- ASUS motherboard using an AMI APTIO IV or APTIO V BIOS.
- The .CAP version of the BIOS you want to flash.
- An MS-DOS bootable USB or equivalent (use Rufus if you need to make one)
- AMI Firmware Update APTIO IV or V, whichever your board uses (or download both)
- ASUS BUPDATER.EXE. I found mine in the downloads section for my host motherboard.
- First & foremost, it would be best for you to make a backup in case you make a mistake.
- Extract APTIO Firmware Utility somewhere then navigate to \afu\afudos and extract (again) AFUDos.
- Copy AFUDOS.EXE to your DOS bootable USB (do both versions if you’re unsure, I named one AFUDOS4.EXE and AFUDOS5.EXE).
- Copy BUPDATER.EXE and your BIOS.CAP file to your DOS bootable USB.
- Make sure you have Legacy Mode enabled in the BIOS and boot from the USB.
- After MS-DOS or equivalent has booted, this would be a good opportunity to carefully switch BIOS chips (only if you are using this guide to hot-flash a different chip).
- Run: AFUDOS.EXE BIOSNAME.CAP /X
- Run: AFUDOS.EXE BIOSNAME.CAP /X /B
- Run: AFUDOS.EXE BIOSNAME.CAP /X /N
(These commands might also run together as “AFUDOS.EXE BIOSNAME.CAP /X /B /P /N” but I’m just posting my exact steps for how I got it working).
If you are using an Intel motherboard you might also have to do AFUDOS.EXE BIOSNAME.CAP /X /ME /MEUF or something (I was using AMD, so it wasn’t necessary).
- If all those succeed, run BUPDATER.EXE /G
In the top left corner it should now show your new ROM info.
Select your BIOSNAME.CAP and hit enter, follow the prompts.
* This step may be redundant, but mine wouldn’t POST without doing it for some reason.
- After this completes, voila, you now have a different ASUS BIOS on your BIOS chip and you didn’t need to buy a flash programmer (but I really should one day).
If anyone tries this with an Intel motherboard and the process needs to be amended, please feel free to add on to this guide.