Flickering Display after Update Ubuntu 18.04 LTS to 20.04 LTS

[Ubuntu_LTS_user]

I updated Ubuntu 18.04 LTS to 20.04. LTS last week and now I do have a flicking problem, too. My tower-PC starts OK and then begins to flicker. Flickering gets worse the longer I work on the system.
I don't think that it is a reason for the problems but I removed libomp5 before the update to 20.04 LTS on 18.04 LTS according to the release notes of 20.04 LTS that say that for Ubuntu 18.04 systems with clang-6.0 and pocl-opencl-icd it is not possible for the release upgrader to calculate the upgrade to Ubuntu 20.04 and propose to workaround this by removing clang-6.0 or libomp5.

As jglen490 asked in a similar thread for hardware infos inxi -Fxxx told the following.

Could somebody help?

System:
Host: XXXXX Kernel: 5.4.0-52-generic x86_64 bits: 64
compiler: gcc v: 9.3.0 Desktop: Gnome 3.36.4 wm: gnome-shell
dm: GDM3 3.36.3 Distro: Ubuntu 20.04.1 LTS (Focal Fossa)
Machine:
Type: Desktop Mobo: MSI model: Z170A PC MATE (MS-7971) v: 2.0
serial: <superuser/root required> UEFI: American Megatrends v: A.20
date: 07/17/2015
CPU:
Topology: Quad Core model: Intel Core i5-6400 bits: 64 type: MCP
arch: Skylake-S rev: 3 L2 cache: 6144 KiB
flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
bogomips: 21599
Speed: 800 MHz min/max: 800/3300 MHz Core speeds (MHz): 1: 800 2: 800
3: 800 4: 800
Graphics:
Device-1: Intel HD Graphics 530 vendor: Micro-Star MSI driver: i915
v: kernel bus ID: 00:02.0 chip ID: 8086:1912
Display: x11 server: X.Org 1.20.8 driver: intel
unloaded: fbdev,modesetting,vesa compositor: gnome-shell
resolution: 1920x1080~60Hz
OpenGL: renderer: Mesa Intel HD Graphics 530 (SKL GT2) v: 4.6 Mesa 20.0.8
direct render: Yes
Audio:
Device-1: Intel 100 Series/C230 Series Family HD Audio
vendor: Micro-Star MSI driver: snd_hda_intel v: kernel bus ID: 00:1f.3
chip ID: 8086:a170
Sound Server: ALSA v: k5.4.0-52-generic
Network:
Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
vendor: Micro-Star MSI driver: r8169 v: kernel port: e000 bus ID: 06:00.0
chip ID: 10ec:8168
IF: enp6s0 state: up speed: 1000 Mbps duplex: full mac: d8:cb:8a:9b:af:c0
Drives:
Local Storage: total: 4.09 TiB used: 156.88 GiB (3.7%)
ID-1: /dev/sda vendor: Crucial model: CT500BX100SSD1 size: 465.76 GiB
speed: 6.0 Gb/s serial: 1507F0034526 rev: MU01 scheme: GPT
ID-2: /dev/sdb vendor: Western Digital model: WD40EZRX-00SPEB0
size: 3.64 TiB speed: 6.0 Gb/s rotation: 5400 rpm serial: WD-WCC4E5ZYK4AK
rev: 0A80 scheme: GPT
Partition:
ID-1: / size: 448.15 GiB used: 12.52 GiB (2.8%) fs: ext4 dev: /dev/sda2
ID-2: /home size: 480.49 GiB used: 144.36 GiB (30.0%) fs: ext4
dev: /dev/sdb1
ID-3: swap-1 size: 7.89 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/sda3
Sensors:
System Temperatures: cpu: 38.5 C mobo: 29.8 C
Fan Speeds (RPM): N/A
Info:
Processes: 233 Uptime: 21m Memory: 7.66 GiB used: 1.90 GiB (24.8%)
Init: systemd v: 245 runlevel: 5 default: 2 Compilers: gcc: 9.3.0 alt: 9
clang: 10.0.0-4ubuntu1 Shell: bash v: 5.0.17 running in: gnome-terminal
inxi: 3.0.38

 

[KGIII]

This is rather old - but I've seen it be the solution in the past. I've tried linking to the exact post.

https://ubuntuforums.org/showthread.php?t=2339302&p=13553913&viewfull=1#post13553913

If it doesn't help, you can undo it. Don't forget the update-grub step.

 

[wizardfromoz]

Just a heads up on the above Post.

@KGIII - looks like a tip worth trying, but needs a modification to the command listed in the link, which says

gksudo gedit /etc/default/grub

gksu and gksudo were deprecated (made obsolete/redundant) from Ubuntu 17.10 'Artful Aardvark' onwards. (Likewise kdesu and kdesudo under KDE desktop environment)

You can read about that here

https://itsfoss.com/gksu-replacement-ubuntu/

So that line should have an "admin://" placed in front of the file to be edited, that is

gedit admin:///etc/default/grub

gedit is only for GNOME, which the OP is using.

While the file is being edited, Terminal will remain open until the exercise is finished, when it reverts to its prompt.

Alternative is (if installed, and policy is set)

pkexec gedit /etc/default/grub

Cheers and enjoy your Linux

Chris Turner
wizardfromoz

 

[KGIII]

To add to the above, I'm a more 'sudo nano /path/to/file' kinda guy.

Learning to comfortably use nano is worth the time invested.

 

[jglen490]

To add to the above, I'm a more 'sudo nano /path/to/file' kinda guy.

Learning to comfortably use nano is worth the time invested.

Truly! nano is a beautiful thing.