What GPUs do you use for game development with UE4?

Oh, i see the break down now. Hmmm … wow, this could really go either way
I would 100% stay away from using a GAMING card as it can really mess with 3d rendering (apples to oranges here)
Now, the real question is, “is CAD a primary CUDA render?”. I think it is. I would need to double check

If CUDA support then nvidia
If Stream support then ATI/AMD

it really depends on the apps you are using, but, i wouldnt get a desktop gaming video card for any 3D design … if you MUST, then, i would stick with whatever CAD supports.