I want to use the GTX1050, so I set gpu-index to 1. Only 1 CUDA device so I set cuda-index to 0. To use the OpenCL device for the GTX, I looked at the bus # (bus 2), found OpenCL device on bus 2 (device 0), so I set opengl-index to 0. Not sure if this is the right way, but it worked for me.
SpikedCola|6 years ago