I use cudnn cuDNN v5 (May 12, 2016), for CUDA 7.5.
my cuda version is :
nvcc  --version
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2015 NVIDIA Corporation
Built on Tue_Aug_11_14:27:32_CDT_2015
Cuda compilation tools, release 7.5, V7.5.17

How can I find more details about the cudnn?