Modded bios if you boot in uefi mod dont work.
Only if you mod also uefi gop and then of course no secure boot.
I updated the gop tool to update your polaris card with modded 1.69.15.50 that makes the card to work in uefi mode. Of course disable secure boot.
GOP Updater v1.9.6.5.d - magic amd gop.rar (5.5 MB)