Metal compatible NVIDIA card not working under Mojave because no web driver
I have a mid 2012 Mac Pro and an NVIDIA Geforce GTX960 running fine under High Sierra, and it states under System Information that this card is metal compatible, and gives a Metal version number. According to the instructions here: https://support.apple.com/en-us/HT208898 this card should work in Mojave. All it needs is a web driver, and NVIDIA have said they're able to provide one but that it is up to Apple to approve their web drivers. Please refer to this for the whole sorry saga:
https://en.wikipedia.org/wiki/Nvidia#Apple/NVIDIA_web_driver_controversy
Mac Pro, macOS 10.13