Please - avoid GPU from AMD if you keep in mind rendering on GPU in any sense.
you can buy 3900x (it fast enough)
you can buy 32GB RAM instead (is enough for 70-80% of scenes)
you can buy simplest and more cheap SSD (there is no such difference)
but please do not buy AMD GPU!
even in luxrender now CUDA faster than openCL
1- Octane - cuda ONLY
2- Fstorm - CUDA ONLY
3- REDshift - CUDA ONLY
Cycles
AND
AND
Even Marvelous Designer simulations say NO to AMD
and so on…
OPTIX on nvidia it is must! http://prntscr.com/t79zqx
-https://forums.luxcorerender.org/viewtopic.php?f=5&t=2283&p=23633
