As mentioned in the title. Was upgrading from 17.10. Having this screen flickering.
My GPU is AMD RX480
What I did:
- Search for similar issues for 18.04, can't find any
- Perform fresh install. Still the same.
Please help. It is very annoying. I can't work.
I solved it myself by using
amdgpu.dc=0
as a boot parameter.To do this, edit the file
/etc/default/grub
, for example usingFind the line beginning
GRUB_CMDLINE_LINUX_DEFAULT
and add the textamdgpu.dc=0
between the double quotes (""
). Leave any other parameters as they are. For example, you may end up with a line like this:Save the file and exit, and then run
to write the configuration, and reboot.
I have screen flickering problem when I'm connecting my laptop to my TV. I found that when I change the refresh rate from 60Hz to 59Hz this problem disappear.
Within Xorg (as I know 18.04 uses it by default) you can change the refresh rate by the help of
xrandr
:0. First you must find the video output name to which you should assing the new mode. Just type
xrandr
and investigate which one is it. In my case this isHDMI-1
.1. Generate new modeline using
cvt
:1920
and1080
are the horizontal and vertical resolution's values.59
is the value of the refresh rate.2. Create the new mode:
3. Assign the new mode to the video output:
4. Activate the new mode:
If the above works and the problem disappear, you should find a proper way to add and set this mode at the system startup. Here are few references about that:
xrandr
customization permanent?I've no answer here, but some observation and confirmation of problem. If someone finds this text: please stick to ubuntu 17.10 if you have radeon rx 580 (may be 480 and vegas)
Got myself to very same situation with 18.04 (upgrade, then fresh install). Amd rx 580 here, kernel 4.15.0-20.
What did not help:
Update: Apparently older kernel works. I've been tinkering with other distibutions and found that kernel 4.15.14 works for rx 580, you may want to try it from mainline ppa.
I faced a similar problem,I wasn't able to log in with the graphical mode at all, I solved it by :
1- enter to tty mode (ctrl+alt+f5, en my case)
2- adding open grafic Drivers (https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers):
3- reboot
6- reboot and it works fine!!4- enter into tty mode again
5-
hope it helps.
Turn off the automatic brightness control to fix this.
Just got 4.19-rc1 kernel installed and flickering is completly gone, no need to restart PC no other magic - it works out of the box.
I'm using Arch now, but believe ubuntu's mainline kernel going to provide same experience. http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19-rc1/
I had the same issue with my RX580 (Kubuntu 18.04, Plasma 5). The flickering only started when the GPU got higher load (playing the Witcher 3 in my case).
First I installed the 4.19 kernel (which has amdgpu.dc=1 by default).
That alone didn't seem to help but maybe contributes to the fix.
Than, I set the screen refresh rate to 59.xx hz with the KDE monitor settings GUI.
After this, the problem seems to be fixed.
In my case the flickering started when I manually switched screen resolution with xrandr (without an explicit refresh rate setting), so maybe the refresh rate was misconfigured by those commands and only the refresh rate needed to be fixed.
I have RX460 and the same problem. Changing kernels or installing amdgpu-pro drivers didn't solve the issue.
The only way I could get rid of the flicker is to set the refresh rate from 74.9 to 60Hz.
Had the same issue myself. It might have been the kernel, but what fixed it nicely for me was leaving all the defaults on (including refresh rate) and going into my monitors settings and disabling FreeSync.
Installing liquorix kernel 5.2.0-27 on debian 10.1 solves the screen flickering at 75hz ,for my rx550