I was shopping around for a new computer solution, one that would allow me to handle most of my computer needs. I have a mid-2011 Mac Mini, i5, with 16 gig memory. For the most part, that handles my computer power fairly well. It does fall down on the job in graphics, being very slow with the onboard Intel graphics chip.
So I knew I wanted to go to native 4k, and 30 bit color if available. Currently there are very few 30 bit color solutions on Mac. There may be some in the future if you believe MacRumors, but nothing coming down the line soon.
I also wanted to get a better GPU performance out of the system.
In the end, I decided to keep the computer i have, and I purchased a BizonBox2s from BizonTech with the NVidia Titan X Maxwell card. Yes, I probably could have put together the external PCI-e box myself with the graphics card, but I am willing to spend the money to have someone else handle that and give me a warranty. And it seems to work fairly well.
I am able to run X-Plane (a flight simulator) at 30 fps in 4k at highest detail. Prior to this point I was only able to run 30 fps in 1k and mediocre detail. It's nice to see car lights on the road at night when you're virtually flying :) It makes using Blender much faster, so I can model pretty much in real time rather than needing to wait for the screen to updatrre.
And, the integration was good. Other than needing to change OS-X security settings, difficult when you have a wireless keyboard, their activation software worked very well. It took the time to download the drivers, set them up, and now I can plug my thunderbolt 1 port into the BizonBox2s and my 4k monitor into the GPU. It works. The screen doesn't show up immediately when I boot, it takes a little more time. If I had 4 displays, I could run them all on this one card. And, I can use the same card for my Macbook Pro, my Macbook Air, and Mac Mini. Since they can all connect via the thunderbolt port.
I understand that most high-end NVidia cards support 30-bit color when using DirectX, but not OpenGL. I am hopeful that will get resolved in the near future.
The only real problem I have found is that when I shut down there is sometimes a kernel panic. I suspect that will get worked out. Well, the other problem is that my cat wants to try to sit on it. It's just not wide enough for her.
A minor annoyance is that I can't use the pass-through port on the BizonBox2s, and it has to be directly attached to the Mac Mini. I can live with that.