All the GPU logic uses OpenCL. Please check if your GPU supports it,  maybe a driver update is needed.

You can use the following to check your GPU:

1.  open https://developer.nvidia.com/opencl
   
2. download and execute OpenCL Device Query

You can also check the gpu directory in case, you can select the gpu but errors are thrown:

1. Click on Settings > Open save place
   
2. Navigate into the gpu folder
3. all files should have a size, else something went wrong during compiling