ASUS BIOS Update

Aug 2, 2021
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It's 2021, and I', still searching the web to solve this particular problem: update the BIOS of a old Asus P5GC-VM/SI motherboard.

Asus provides BIOS updates only for the standard version of P5GC-VM; the /SI identifies a customized version of the board (in my case, a Telecom Italia horrible computer).

After a couple of days of bestemmie dure, I've managed a way to update the BIOS with a standard one. This is what I've done.

1- First of all, get a working floppy disk drive and a blank floppy disk. This is the hardest and more smadonnamenti prone part.
2- Download the last BIOS from the Asus website for the P5GC-VM motherboard and tienilo in caldo. Download also the DOS utility to flash the BIOS, it's called AFUDOS or something like that. You can get it from the Asus website too.
3- Connect the floppy drive to the motherboard and put the floppy disk on it. Power on and press ALT+F2 like non ci fosse un domani.
4- The motherboard should start in the EZ Flash mode, and checking for a file named P5GC<something>.ROM on the floppy disk. Note down the name of the file the system it's looking for.
5- Create a pendrive with a bootable MS-DOS system (you can use Rufus, for example), and copy on it the AFUDOS utility and the new BIOS ROM file. Boot the system using the pendrive.
6- Create a copy of the current BIOS using AFUDOS.
7- Open both the current BIOS and the new one with a hex editor (I use HxD Hex Editor). Go at the bottom of the original BIOS, copy the motherboard model name and the ID code, and overwrite the same informations in the same position of the new BIOS. Save the new BIOS on the pendrive using the name EZ Flash looks for (step 4).
8- Boot again the system in DOS mode. Copy the new BIOS file on the floppy disk.
9- Reboot again and press ALT+F2. Now EZ Flash should load the new BIOS from the floppy, and update it.
10- Boot once again, enter the BIOS pressing DEL and check if your BIOS had been correctly updated. The name of the motherboard model may change after the update and loose the customisation part (like the /SI)
11- If everythin worked, grab a cold beer, you deserve it. Otherwise, bestemmia davvero male.

D.