Thanks Fabio for this excellent guide! I got my hackintosh working! I'm using 3970x, 5700XT GPU passthrough, and MP600 NMVE passthrough. Performance is great.
I'll share some tips to get the 5700XT GPU passthrough working. This can be helpful for other people using AMD GPUS. I had to do some extra things:
The default GPU BIOS doesn't have UEFI enabled. Instead of updating the firmware, which is risky (or non existent tools) , you can download a ROM with UEFI support and let proxmox load/expose it when starting the VM. In my case I downloaded this rom (https://www.techpowerup.com/vgabios/212439/gigabyte-rx5700xt-8192-190616). You have to copy it to
/usr/share/kvm/5700xtcustom.rom
and specify the ROM file in the GPU pcie passthrough line vm conf:
hostpci1: 03:00,pcie=1,x-vga=1,romfile=5700xtref.rom
Additionally, I had to enable some extra flags in clover or it didn't boot correctly.
Make sure that you pass the agpmod=pikera boot argument. In graphics settings enable RadeonDeinit. Make sure that InjectATI is correctly disabled. If you are using clover configurator press the checkbox twice, otherwise it's enabled by default.