I know, I know, There has been much talk about the problems of CUDA and AMD in MAc OS, but as much as I read I remain somewhat confused and I would like that, beyond the debate between Mac or PC, I would definitely clarify some doubts concrete.
I’m thinking of buying an iMac 27 with the Radeon Pro Vega 48 8GB, it wouldn’t be just to work with Blender, and my doubts are:
Will Eevee work correctly?
Can I use GPU to render?
What about AMD ProRender? I understand that it is a render engine like Cycles and Eevee
Right now I have a 2013 iMac with an NVIDIA GeForce GTX 780M 4 GB and, as you know, CUDA does not work, so neither Eeve nor GPU
I don’t think Eevee will work all that well. I tried some of the demo scenes in 2.81 on my Trashcan and I saw a bunch of visual glitches that are not present on my Windows PC. I imagine its an OS thing more than a specific GPU issue.
No idea about rendering at all. Didn’t bother to try after seeing what Eevee did.
Cycles will not be able to use the GPU under macOS. Eevee should work. ProRender will work.
You can also partition your drive and install Windows/boot camp or Linux, there your iMac will work just like a regular PC with Vega GPU - including Cycles.