ElPapa wrote:
As an aside if you just want a 'plug it in and forget it' option you can get the Sapphire HD7950 while they're still available.
https://eshop.macsales.com/item/Sapphire/100352MAC2/
I bought one and swapped out the stock card. It's been a solid performer.
I upgraded to a HD7950 as well. It is officially supported via built-in drivers including support for the new Metal API. The only drawback is that Adobe software prefers Nvidia cards due to using CUDA. However apparently the very latest Adobe Creative Cloud updates do now support Metal, it is not yet clear i.e. I have seen no end-user reports as to how much of an improvement Metal support by Adobe delivers.
A couple of other issues, the HD7950 is capable of doing 30bit colour i.e. 10bit color per pixel, this does indeed work in Windows 10 via Boot Camp but sadly Apple have not enabled it in OS X. Secondly the card is capable of sending audio via Displayport and HDMI, again this works in Windows but again Apple have not enabled it.
There is a free third-party KEXT which can enable the audio but it is not signed so you have to turn off SIP to get it to work, there is no equivalent solution to enable 30bit color.
It would be helpful if people could send feedback to Apple requesting these two features be supported.
As a comparison a Nvidia GTX-680 does not support 30bit color even in Windows 10, and while I have so far only done very limited testing while audio again works in Windows 10 via Boot Camp I could not get it working even with the afore mentioned KEXT.