UEFITool

UEFITool is a program for viewing and editing BIOS and UEFI installation files. With it, you can access all of the code behind your motherboard's image in hexadecimal, as well as make modifications to it.

Although motherboard images are commonly called BIOS, most computers today use UEFI, which stands for Unified Extensible Firmware Interface. This offers a greater number of settings on the motherboard, as well as other improvements, such as using a mouse to navigate its menus.

With UEFITool, you can open your motherboard's update file to check its structure, verify its integrity before flashing it, or, most importantly, make modifications to the image. However, it's important to know what you're modifying, because if you flash an incorrectly modified file, you may be left without a motherboard or be forced to run recovery mode to flash an original firmware from scratch.

The tool on which UEFITool is based is somewhat old, so some motherboard firmware may not work. Also, some motherboard images are encrypted, in which case UEFITool won't be able to open them.

So, if you want to make modifications to your motherboard image, downloading UEFITool is one of the best ways to do so.