CAD workstation

Greetings fellow Humans,

I'm building a workstation for an Architect. Prime goal is stability (so no overclocking) and the most CPU speed I can get for the money. Budget is € 600. The software he uses is ArchiCAD (OpenGL) for designing and Artlantis or Cinema4D for rendering. Neither Artlantis nor C4D support OpenCL or Cuda.

My Questions: Is it worth getting a "professional" graphics card? What CPU would you recommend?

I need everything except perephials, Mainboard, Mem, Storage, Case, etc... Memory is going to be 16 GiB, the models can be huge. Any other suggestions?

Thanks

when i was using AutoCAD i had just a midrange system (amd) and everything ran smoothly.

don't know anything about rendering dough.