Petition of Help, non-UEFI MoBo

[Archduke]

Hi, hope you all are doing well, I need some help with my PC, I have a non-UEFI motherboard, Gigabyte 990FXA-UD5 to be exact and I can't make the USB to even boot. I have followed the guide to the letter but just don't know what to try next. I have tried Catalina and Big Sur, both with same results.
The BIOS is already configured as recommended in the Guide, someone have similar issues or know how to deal with this issue?
Sorry for my English.

CPU: FX8320
GPU: Radeon RX480
MOBO: Gigabyte 990FXA-UD5
SSD 120GB to install MacOS

Thanks in advance.

 

[Shaneee]

From what I can tell you'll need access to macOS for a legacy install. You can use a VM to do this, https://dortania.github.io/OpenCore-Install-Guide/installer-guide/mac-install.html#legacy-setup