No matter how I reinstall the CUDA driver and toolkit, when typing gpuDevice(), it always show s:
CUDADevice with properties:
Name: \'Quad
You can also use CUDA 6.5 with matlab under Windows. The tricky part is, you need to compile the mex files under Visual Studio rather than inside matlab. There are numerous tutorials introducing how to compile mex under VS so there is no need to repeat here. You need only to create a NVIDIA cuda project with .cu as the source, and follow the standard procedures to compile mex.