There is a difference between a "gaming" graphics card and a "professional" graphics card. There is a reason why professionals (rendering, animators etc) go for Quadro cards for their workstation usage and why there is a market for these. Besides the OP had made it clear that he won't be gaming.
Slight OT: It is not suggested to upgrade to the R9 380/390 from the R9 2XX because, as many sites have already said, they are rebadged models with minor improvements. So basically if you have an R9 2XX card you can just say "screw the 3XX" and not upgrade it.
