pip uninstall protobuf
pip uninstall tensorflow
pip uninstall tensorflow-gpu
pip install --upgrade --force-reinstall tensorflow-gpu
So for me with 2 GPUs it would be
export CUDA_VISIBLE_DEVICES=0,1
C:/Users/dlink/AppData/Local/Programs/Python/Python35/python.exe -m pip install tensorflow-gpu -i <https://pypi.douban.com/simple/>
国内安装时可用-i <https://pypi.douban.com/simple/
豆瓣源加速>