Apple announced support for external graphics cards in their 2017 WWDC keynote coming to Mac OS High Sierra which comes out in the fall. I unbox it, set it up and run a few tests.
Apple eGPU: https://developer.apple.com/development-kit/external-graphics/
Support ZOLLOTECH on Amazon: http://amzn.to/2jxmglN
Gear I use: http://kit.com/Zollotech/zollotech-gear
Recent Wallpaper: http://imgur.com/bqES8LV