Just installed a MSI RX 470 ARMOR OC 8GB card in my 2009 Mac Pro. Works right out of the box except for it appears as R9 XXX in About and as far as I can tell it is only operating at PCIe 1.0 x16. I was able to "fix" about by editing the controllers so it says RX 470 now but haven't fixed the graphics acceleration even through kext edits that were needed before 10.12.6 which is what I'm on. Everything I'm finding seems to say it should just work completely so I'm trying to see if anyone else has any more ideas. Thanks in advance!