Unsure if this is related, but I'm seeing the same issue with both the 21.04 vendor kernel and 5.13.8. I have a 165 Hz screen, and the Intel iGPU will only run it at 60 Hz. If I switch to the discrete Nvidia GPU in the BIOS, I get 165 Hz and I'm able to switch to 60 Hz.
First I switch from "165 Hz" to 60: Aug 5 10:59:12 ukyo kernel: [ 247.263181] [drm:drm_mode_debug_printmodeline [drm]] Modeline "": 60 282670 2560 2608 2640 2720 1600 1603 1609 1732 0x0 0x9 Aug 5 10:59:12 ukyo kernel: [ 247.263307] [drm:drm_mode_debug_printmodeline [drm]] Modeline "2560x1600": 60 282670 2560 2608 2640 2720 1600 1603 1609 1732 0x48 0x9 Aug 5 10:59:12 ukyo kernel: [ 247.263521] [drm:drm_mode_debug_printmodeline [drm]] Modeline "2560x1600": 60 282670 2560 2608 2640 2720 1600 1603 1609 1732 0x40 0x9 Then I attempt to switch from 60 Hz to 165 Hz: Aug 5 10:59:22 ukyo kernel: [ 257.078950] [drm:drm_mode_debug_printmodeline [drm]] Modeline "": 165 777340 2560 2608 2640 2720 1600 1603 1609 1732 0x0 0xa Aug 5 10:59:22 ukyo kernel: [ 257.079075] [drm:drm_mode_debug_printmodeline [drm]] Modeline "2560x1600": 60 282670 2560 2608 2640 2720 1600 1603 1609 1732 0x48 0x9 Aug 5 10:59:22 ukyo kernel: [ 257.079266] [drm:drm_mode_debug_printmodeline [drm]] Modeline "2560x1600": 60 282670 2560 2608 2640 2720 1600 1603 1609 1732 0x40 0x9 I've tried adding a custom modeline to Xorg to work around this. It sees the modeline, but it doesn't do anything. I'll try the EDID hack. If the Nvidia driver is able to do it, probably something wrong with the EDID parsing if the EDID hack works? My previous laptop (which I replaced just 2 days ago) didn't have this problem. However, it was a i7 10875h with a 144 Hz screen. The new laptop is a Tigerlake 11980HK. Maybe it's the difference in refresh rate or my case of a bug with the newer iGPU? I'll research to see if any of my monitor outputs go through the Intel GPU and I can test against one of my 144 Hz external monitors. Oliver, If you file the bug upstream or already have, can you please share the link? Thanks! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1848746 Title: Refresh rate change requests to 40Hz are "adjusted" back to 60Hz To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1848746/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs