Ubuntu screen flickering
I also had the same problem with a fresh install of Ubuntu 20.04 on my desktop with Intel Corporation UHD Graphics 630 graphic card and 2 Iiyama North America 27'' screens (see the attached image to have a feeling of the flickering I was experiencing).
My problem has been solved simply (thanks to Daniel Van Vugt) by using Wayland display server on the logging screen: Click your profile > Click the white wheel in lower right corner > Choose 'Ubuntu on Wayland'.
This change replaces the use of the xorg display server which seems to make a lot of arguing on the web. I have to admit that explaining exactly why this solves the problem is a bit out of my league, but I let this to other Linux experts in the community. You can also find deeper technical explanations of xorg/wayland by following these links:
- Why is Wayland better?
- Wayland v/s Xorg : How Are They Similar & How Are They Different
Try this one it could help you out: flickering screen ubuntu 18.04.1 LTS
Create an empty file anywhere using right-click menu. Name it 20-intel.conf Open it using any text editor (like Gedit, Mousepad etc.) and add the following lines:-
Section "Device"
Identifier "Intel Graphics"
Driver "intel"
Option "AccelMethod" "sna"
Option "TearFree" "true"
EndSection
Now save the file. Open your file manager with root privilege (sudo -i nautilus for Ubuntu). Paste the file in /etc/X11/xorg.conf.d
Create the requisite folders if they don’t exist. Restart the system after it’s done.
If you experience issues like pixelated graphics, corrupt text, etc. after this, replace the word sna with uxa within the text.
Changes on x11 parameters do not work. What works for me is to change the rasterization settings in chrome. Open the flags page in chrome: chrome://flags, then change the "GPU rasterization" flag to "enable". To be redone after each chrome update.
I was experiencing a continuous small-intensity flickering after a clean install of Xubuntu 20.04 on my laptop (nvidia-driver-455 installed from the graphics-drivers ppa). I think I have solved it by applying the settings below in NVIDIA X Server Settings (toggle first the Advanced view) and clicking Save to X Configuration File. Hopefully, it can be of help.
I had the same problem, but in my case I went to boot menu, I selected the same drive containing my ubuntu OS, then selected ubuntu boot advanced option, chose repair packages. This fixed the whole flickering issue.