This is my first system I have put together. I have a very similar system GTX 970 and GA-Z170X-UD5, but no matter way I do I can't get the Nvidia Web drivers to load. I have uninstall and reinstall so many times I don't remember how many times. 10.2.1 was out when I installed so I started there, system definition is set as iMac 14,2. I have tried editing the config.plist using EFI mounter V3 and Textedit and that makes no difference. I also tried using Clover Configurator and removing nvda_drv=1, and it still didn't load the drivers. I also tried updating to 10.12.2 and using the newer Nvidia web drivers and that resulted in the exact same issue. I reinstalled back to 10.12.1 and any help would be much appreciated.