First up are a few different OpenCL test profiles. AMD results are not available for these GPGPU results since the AMD OpenCL/APP SDK was being problematic under Linux at the time, which is not too surprising. NVIDIA, on the other hand, usually always has great OpenCL/CUDA SDK support in place for Linux.
The JuliaGPU OpenCL test is substantially faster than the GeForce GTX 460 / 550 Ti Fermi hardware.
The performance-per-Watt out of the GTX 680 was also easily the best out of any of the four tested NVIDIA GPUs.
The GTX 680 though was also much warmer than the other mid-range GPUs with its average temperature for the JuliaGPU OpenCL workload being 65C.
The AMD FX-8150 + GTX 680 system power consumption for the OpenCL workload was about 235 Watts.