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So, what's the better route on KS9? Something like a 32 core Threadripper 3970X CPU or a fast GPU like the Quadro RTX 8000
Both are fantastic for KeyShot. For typical product shots, the RTX 8000 is going to be
very fast.
However, you won't hear Luxion explicitly recommending GPU over CPU. CPU rendering does have benefits. Complex shaders like Cutaway are currently only supported on CPU. Caustics are currently more optimized on CPU. CPU has access to all available RAM. CPUs are not reliant on drivers like GPUs are.
You have to decide for yourself what kind of KeyShot user you are and whether those CPU benefits are relevant to you. If not, then maybe RTX 8000 is a good choice for you.
Dries