I have been using this machine with 24.04.3 LTS for quite some months and just recently plugged it into an external monitor (Gigabyte G24F).
When I run it on 120hz, the monitor screen jitters at times. Even if I lower refresh rate to 100hz, it still stutters on the external monitor, but as soon as I make it 60hz, it works well.
I am on wayland session. I had tried X11 but it is much worse with the jitters.
My laptop specs are:
Dell latitude 7490, I5 8250U, 8gb ddr4 ram and 256gb ssd.
I saw on the web that this was some issue with intel 7th and 8th gen, especially with Intel UHD 620/630 Graphics. So I tried the fix as was outlined here:
https://mohessaid.medium.com/how-to-fix-screen-flickering-in-ubuntu-24-04-lts-8546f26ca55d
Basically I changed this parameter in /etc/default/grub:
From:
GRUB_CMDLINE_LINUX_DEFAULT=“quiet splash”
To:
GRUB_CMDLINE_LINUX_DEFAULT=“quiet splash intel_iommu=igfx_off i915.enable_psr=0 i915.enable_fbc=0”
But even after doing this, the screen still stutters, although less frequently than before.
Then another post said to try an OEM kernel, and I installed: 6.17.0-1005-oem kernel (linux-oem-24.04d package), but it still hasn’t fixed it.
Also I have noticed is that when i run testufo.com , it doesn’t show full 120 fps, rather fluctuates in the range of 110-115 fps.
To rule out hardware issue, I tried it with windows 11 and it works perfectly fine there. I even tried an old 24.04.3 live image i had from several months ago in a usb stick and that seems to work alright and even gives 120fps on ufo fps test.
What should I be doing in such a case to fix this issue?
Thank you