DX12 isn't helping performance for either vendor. Does it work in DX11? The 16.9.1 drivers gave a hefty boost in DX11 as well, so if you can get it to work in DX11, then just play it in DX11.
DX12 is actually performing worse than DX11 in almost every bench I've seen.
Have you got a freesync monitor?
DX12 looks better and minimum are a lot better but I need cfx at 4k
Nah, I wish.