Tech Monger

If you have freshly installed Ubuntu 16.04 LTS or upgraded from previous version of an Ubuntu then you might face issue of black login screen on startup. Ubuntu will boot up normally but you will get stuck during user login with black windows. This issue occur due to incorrect default graphic configuration during installation or upgrade. Follow step by step guide to solve this issue. This solution is only applicable to the AMD graphic card using radeon drivers. However you can follow same solution by substituting modeset for your graphic driver.

When you face black login screen after bootup your computer will still remain running with Ubuntu. However Ubuntu would unable to render graphics on screen. After getting black screen follow this steps to resolve it.

1. Open terminal by pressing Ctrl+Alt+F1 on keyboard. You should see login prompt on shell. Enter your login credentials.

2. Once you are logged in you have complete access to shell. Now update ubuntu local repository and upgrade packages. It will take considerable time.

   sudo apt update

   sudo apt upgrade

   You will not be able to update packages if you do not have Internet connection or you have not configured wifi during installation. But you can still follow along if your driver is installed during installation or with nomodeset configuration.

3. After installing packages make sure graphic driver is installed and can be invoked by shell.

   man radeon

   Above should open man page of radeon. If you are using graphic driver other than radeon then you should invoke it yourself.

4. Edit the grub configuration to use radeon as graphic driver.

   • Open grub configuration file

      sudo nano /etc/default/grub

   • Change the value of GRUB_CMDLINE_LINUX_DEFAULT
     From

     GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

     To

     GRUB_CMDLINE_LINUX_DEFAULT="quiet splash radeon.modeset=1"

   • This configuration change will force linux kernel to use radeon as graphic driver. If you are non radeon user then you should set modeset value for your graphic driver.

5. Update the grub after making above configuration change

   sudo update-grub

6. Shutdown machine and restart it. You may need to wait for a while for machine to cool down if it is getting overheated.

   shutdown now

If blank login screen reappears after restart then you may want to temporarily set nomodeset in grub configuration and try again. Replace GRUB_CMDLINE_LINUX_DEFAULT in step 4 with following line and follow subsequent steps.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

If issue resurfaces after reboot then restore value of GRUB_CMDLINE_LINUX_DEFAULT in grub configuration and check for the correct configuration of graphic driver.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

sudo update-grub