The extra-painful part about this whole situation is that it's apparently only due to Apple blocking NVIDIA from signing and publishing their drivers. (for whatever bizarre reason they may have to do that)
Nvidia blocks the Nouveau drivers from working properly on Maxwell2 or newer cards: https://www.phoronix.com/scan.php?page=news_item&px=Nouveau-...
I currently run an EVGA 980Ti Classified in my hackintosh. It’s great hardware, but with the frequency of glitches that the drivers bring I’m increasingly inclined to sell it and replace it with an AMD card.