How to uninstall the manually installed NVIDIA driver

For more information about how to uninstall the manually installed NVIDIA driver-general Linux technology-Linux technology and application, see the following. My NVIDIA graphics card driver is manually installed by downloading it from the Internet. The installation method is sudo/etc/init. d/gestation stop; sudo sh NVIDIA. run; sudo/etc/init. d/ghd restart; for some reason, you can install these three commands twice. However, it was later discovered that NVIDIA drivers were included in the computer's "additional drivers. So I want to uninstall the manual installation, and then install the driver. The uninstallation process is also the preceding three commands, but an uninstall command is added after the second command (all methods obtained from the Internet ). The result is that the system stays on the load page before login after restart. The page shown below ubuntu. The graphic interface cannot be integrated. I will find a method from the Internet, but want to switch to the command line interface, but my computer press Ctrl + Alt + F1 ~ F6 cannot access the command line. And then reinstalls it. After manually installing the video card driver, I also installed the additional driver. However, if the driver is attached, the driver is active but not in use. I clicked remove under the additional driver. Then restart. Sadly, this happened. The error screen at the front is displayed. I do not know why. Which of the following experts can explain this question. Thank you.