Try upgrading your graphics drivers. http://www.nvidia.com/download/driverResults.aspx/123225/en-us Is the most updated drivers for GTX 960 as of 9/3/2017 for Windows 7 64bit
Before updating I would recommend running DDU to remove all old drivers as they can cause issues. https://www.guru3d.com/files-details/display-driver-uninstaller-download.html
- Download graphics drivers and install to desktop. Do not run it yet
- Extract DDU to desktop and navigate to the folder created then run the executable. It will ask if you wish to restart to safe mode. Say yes to this prompt.