|The nv4_disp.dll is part of the video driver. If your to update it you would as a whole would uninstall your video drivers. Before doings so download the latest drivers. Also download and install Driver Sweeper.|
Run driver sweeper after you run the nvidia uninstaller. Run driver sweeper from safe mode for it to cleanup driver files that the uninstaller didn't remove. After the sweeper has done its job reboot in normal mode and install your new drivers.
Frank Pepper: “Professionals built the Titanic, amateurs the ark”