You can't. CUDA is an nVidia exclusive tech. Not that it matters much - unless you use the Raytrace 3D stuff, it's irrelevant and normal OpenGL functions always work.
So if I upgraded to a supported card would it improve overall performance in after effects? Weird thing is is that it works in Premiere but not After Effects.
So if I upgraded to a supported card would it improve overall performance in after effects?
No. Not at all. Not with the current version of AE, anyway.
The ray-traced renderer was just a clunky way to create 3d natively in After Effects. The ray-traced renderer is considered obsolete. If I were you, I would tick the box to never show that error message again and never worry about it at all. (In fact, that's exactly what I did on my MacBook Pro.) The ray-traced renderer was just a clunky way to create 3d geometry natively inside AE. It didn't make anything faster. In fact, it made everything slower. Since we have a much more powerful way to do 3d in AE, you can happily ignore the ray-traced renderer. (Some great training for Cineware here, by the way.)
AE uses the GPU for very little. GPU (CUDA, OpenGL) features in After Effects See? A GPU is pretty pointless for AE. (Unless you use third-party plugins like Element or Red Giant Universe that render on the GPU, but they will work on AMD cards just fine and don't have anything to do with the ray-traced renderer.
Weird thing is is that it works in Premiere but not After Effects.
Not really all that weird if you look into it. Premiere Pro and After Effects are entirely different pieces of software that work with video footage in an entirely different way under the hood because they both do entirely different tasks.
Thank you for the links. I'll definitely look into them. I do use Element though. Does it automatically render from the GPU?
Yes, it only renders from the GPU.
No dedicated GPU? No Element.
Element works just fine with AMD cards.