(In reply to Michel Dänzer from comment #1)
> Please attach /var/log/Xorg.0.log and the output of dmesg.
> 
> Can you upload the video somewhere?
> 
> If not, please provide more details about the glitches, e.g.: Are they
> always visible, or only intermittently? If the latter, how often? Does the
> vertical location of the glitches change or is it always the same? ...

I set the 120Hz and restarted. Then I opened Konsole and got the results and
put then as attachments.

Finally got a video and put it in Youtube:

https://www.youtube.com/watch?v=W7a9nrwPPeY

I cant get the video with tools like Kazam or SimpleScreenRecorder. I have to
grab it with a external camera.

The glitches are intermittently. The image cam be fine for a fell seconds then
the glitches show themselves.