14

So I installed 19.10 fresh from USB. I picked no login required. First reboot after install I'm welcomed inside Ubuntu. But second time I'm prompted to login for no reason. Worst part is that i login with right password and all but it just loops me back to the login screen again. If I enter wrong password, it tells me I'm wrong. Tried to login via terminal and then type "sudo startx". That just led me back to login screen.

Please help me, I'm running a first gen amd ryzen and nvidia 980ti.

Edit: SOLVED! In my answer below.

Huux
  • 361

4 Answers4

12

I had this issue after upgrading from 19.04 to 19.10.

The solution that worked for me is to switch display manager from GDM3 to LightDM.

If you have installed the lightdm package, just run sudo dpkg-reconfigure gdm3 and select LightDM.

After rebooting you should be able to log in.

I have since found a solution to fix login loop without changing GDM3 to LightDM:

  1. On the login screen, press Ctrl+Alt+F3.

  2. Log in to the shell using your username and password.

  3. Uninstall and reinstall the gdm3 package:

    sudo apt-get purge gdm3
sudo apt-get install gdm3

Now just select GDM3, and after a reboot it should work fine.

Eliah Kagan
  • 119,640
Korni
  • 121
12

SOLVED

That's a problem related to the NVIDIA Kernel Module failing with proprietary drivers. To solve it, do the following steps:
  • At the login screen, press ctrl+alt+f2 to enter the terminal and login with your name and password
  • Type sudo nano /etc/default/grub (you can change nano to the text editor of your preference) to edit /etc/default/grub
  • Change the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="nomodeset"
  • Save the edition pressing ctrl+o and exit pressing ctrl+x
  • Update this grub edit with sudo update-grub
  • Install lightdm using sudo apt-get install lightdm
  • Reboot typing sudo reboot
heynnema
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Huux
  • 361
1

Try to boot in recovery mode (if grub does not show a menu hold shift key while booting). And then remove a gnome shell extension as explained in this answer :

Login loop after upgrading to 19.04

if it does not work, in grub menu press e key to edit boot menu option add nomodeset as kernel parameter at the end of the line which has "Linux" in it.

Linux /boot/vmlinuz... nomodeset

press Ctrl+x to boot.

Gediz GÜRSU
  • 266
0

After installing lightdm display manager and rebooting, I was able to login just fine. 

 sudo apt-get install lightdm

System Specifics:

OS: Ubuntu 19.10,  Kernel: 5.3.0-19-generic
*-display                 
       description: VGA compatible controller
       product: TU104 [GeForce RTX 2080 Rev. A]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:02:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
Display Manager: Gnome Display Manager (GDM)
Driver: nvidia-driver-435
malanb5
  • 161