Results: Luxmark 2.0
I was quite curious about the OpenCL performance of these latest cards. AMD has really been pushing the compute API as of late, especially in advance of their Kaveri APU release. They have a pretty solid OpenCL 1.2 implementation for their GCN based chips. NVIDIA, of course, has been blowing the GPGPU horn as loudly as possible over the years, although they are focused on their CUDA API. Oddly enough, Kepler made compute performance take a back seat to enable better performance and efficiency in graphics applications. I used the 64 bit version of Luxmark 2.0 with the Sala test.
The combination of more stream units, higher clockspeed, and more memory bandwidth makes it so the 280X is the undisputed single GPU leader here. Note how the lower end, but Maxwell based 750 Ti is very close to the older Kepler based 760. My guess here is that the GTX 960 takes those gains and matches, if not exceeds, that of the R9 285.