I have a 780Ti and a 760, and running GPU-Z reports they both support Compute 5.0. I just updated the drivers, and using -d to separate and test the cards one at a time shows the same error with both cards. Any recommendations? As far as I can tell, this is the only version of ccminer I can find which supports the Lyra2 algo (and all your other algo optimizations are also very helpful), so I'd really like to get this to work. Thanks! 
Wouldn't be the first time GPU-Z is wrong on anything
Check your GPU here, under "Cuda-Enabled Geforce Products": https://developer.nvidia.com/cuda-gpus
But I can already tell you a 780ti is compute 3.5 and a 760 is 3.0
