In a previous article I installed Ubuntu 20 and everything works fine. But after last update, few days of using there was a problem with nvidia drivers.
Reinstall and prime switching, removing X11 nvidia config didn't worked for me. Maybe just my bad usage (I used to run other Kernel), but I will show you my way to solve all problems.
During reinstallation of nvidia drivers I noticed, that drivers was installed only for Generic Kernel. So fast check:
$ uname -r 5.4.0-26-lowlatency
Whaat?! I have no idea why, I though that by default is always generic. I never changed it!
Ok but I don`t need lowlatency so I checked my available images:
$ dpkg --list | grep linux-image ii linux-image-5.4.0-21-generic 5.4.0-21.25 amd64 Signed kernel image generic rc linux-image-5.4.0-24-generic 5.4.0-24.28 amd64 Signed kernel image generic rc linux-image-5.4.0-24-lowlatency 5.4.0-24.28 amd64 Signed kernel image lowlatency ii linux-image-5.4.0-25-generic 5.4.0-25.29 amd64 Signed kernel image generic ii linux-image-5.4.0-25-lowlatency 5.4.0-25.29 amd64 Signed kernel image lowlatency ii linux-image-5.4.0-26-generic 5.4.0-26.30 amd64 Signed kernel image generic ii linux-image-5.4.0-26-lowlatency 5.4.0-26.30 amd64 Signed kernel image lowlatency ii linux-image-generic
First I checked linux-image-5.4.0-26-generic by running it from Grub menu (Advanced options). Everything worked fine, except that now my laptop monitor was disabled, and only external monitor works on nvidia. For that just erase whole xorg.conf, don't remove (Im not sure if you can), just leave it empty:
After reboot (still have to select right Kernel from advanced Grub menu) it finally worked fine.
Last I need to set this Kernel to boot by default. I don't want to select right one every time. Fastest way to do it is to edit:
I had GRUB_DEFAULT=0, so I changed this option to:
Updating Grub after editing:
$ sudo update-grub
Now Grub remember my last used kernel. After first reboot select again desired Kernel, because saving option will work after reboot. Second reboot works fine.