Yes Firefly is CPU rendering only, but dynamic cloth is mentioned and there are some GPU (nvidia CUDA) accelerated options out there.

I purposed 3060 12GB since it is the lowest cost HDMI 2.1 and decent amount of VRAM for any future GPU tasks, cloth or rendering. With HDMI 2.1, any new TV or monitor can be run at HDR, high refresh rate, 4k, 8k and so on.

With the 7950x there is a very small iGPU, so an external GPU can be bought later...