Here's one other test I had done previously using a GTX 970 video card and Nvidia drivers.

CUDA 970:

DVD@8mbs - 1150fps
Blu-Ray@24mbs - 385fps

If you want to do some heavy duty transcoding, this will do the job. Mezzmo doesn't support Nvidia and I think this would be overkill but in case anyone is interested. At lower bit rates these numbers go up much higher.