Graphics cards like nVidia with CUDA will only speed up Ray Traced work in After Effects.
Also, RAM previews and renders depend a lot on what effects you are using, etc.
Some effects thread well, some don’t.
I’m currently in the market for a new computer myself.
After a LOT of research and phone conversations with Eric Bowen at ADK, I’ve come to the conclusion that a PC running Windows 7 or 8.1 and a i7 4930K over clocked to 4.5GHz with 64GB of ram will be the best thing for AE over more threads and a dual Xeon machine.
If something doesn’t thread well in AE, then the extra GHz will give it a bigger bump than throwing more threads at it.
Hope this helps,
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