Co-author of the Guide to GPU Blagovest Tasko looks at the new Polaris based AMD card, the RX 480 card.
AMD RX 480 vs Fury X vs GTX 1080 CUDA vs GTX 1080 OpenCL
Comments from Blagovest Taskov:
"We received the Polaris based AMD RX 480 8gb and did a few early benchmarks with it.
For denoising it seems like the best performance per dollar, being 35% faster than GeForce GTX 1080 and 275% faster than Titan X. It is 44% slower than AMD Fury X which is the fastest denoising GPU with the current #VRay denoiser, but it is much cheaper.
There are some very interesting/surprising results with RT OpenCL as well. In most scenes it is less than two times slower compared to the three times more expensive (comparing reference models with same memory configurations) GTX 1080 running CUDA and roughly as fast as it running OpenCL.
There are features that are not supported in the V-Ray for OpenCL engine compared to V-Ray for CUDA. We plan to look at those.
It seems like the older Fury X is performing better with the new drivers as well, but the Polaris architecture is definitely a big improvement."