B85MD3H screen keeps black unless I press F12 to choose before the boot

sorry about my poor English and could you please help me with this.

graphics:amd r9 380x using hdmi;

cpu:e3 1231 v3;

motherboard:gigabyte B85MD3H rev1.2;

I download

B85MD3H.F15-KU_XMAX.rom from forum,but when I install or boot mojave 14.1,the screen keeps black unless I press F12 to choose mac in boot menu before boot.

There are only two boot options with the same name(mac osx) in boot menu,either of them boots when set as the first boot priority in bios default boot order,but both of them work when I press F12 to choose any one of them,which means every time I boot my computer,I need to press F12.Is there any solution to it?

And with mac14,1 the default model,it runs slowly.I changed the model to mac pro 6,1

B85MD3H.F15-KU_XMAX-MODEL_MODED.rom it runs normally,but it displays only top left corner(F12 pressed still needed).

ps:I put whatevergreen.kext and lilu.kext in EFI⁩ ▸ ⁨Efi⁩ ▸ ⁨Oz⁩ ▸ ⁨Darwin⁩ ▸ ⁨Extensions⁩▸Commnon.

thanks very very much.

Here is my OzmosisDefaults.plist.