I made the switch to 19.10 and the problem is the same in the logs. There is a slight difference however, the screen doesn't flicker any more upon the change request. I suppose it now detects the adjusted modeline is the same as the current one, hence nothing to do.
Here's some output extracted from dmesg (ISO date format) : 2019-11-04T16:39:13,088276+01:00 [drm:intel_dump_pipe_config [i915]] requested mode: 2019-11-04T16:39:13,088290+01:00 [drm:drm_mode_debug_printmodeline [drm]] Modeline "": 0 92450 1920 1968 2000 2080 1080 1083 1088 1111 0x0 0x9 2019-11-04T16:39:13,088323+01:00 [drm:intel_dump_pipe_config [i915]] adjusted mode: 2019-11-04T16:39:13,088336+01:00 [drm:drm_mode_debug_printmodeline [drm]] Modeline "1920x1080": 60 140490 1920 1972 2007 2094 1080 1083 1089 1118 0x48 0x9 So it's the current 19.10 kernel (5.3.0-19-generic). I'm considering trying v5.4-rc5. I will report back once (and if) it's done. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1848746 Title: Refresh rate change requests to 40Hz are "adjusted" back to 60Hz Status in linux package in Ubuntu: Confirmed Bug description: Dear Launchpad readers, Changes to a 40Hz-based mode are adjusted back to a 60Hz display mode by KMS, as can be seen in the logs with the drm.debug=4 option : oct. 18 16:27:24 NovHak-P2 kernel: [drm:intel_dump_pipe_config [i915]] requested mode: oct. 18 16:27:24 NovHak-P2 kernel: [drm:drm_mode_debug_printmodeline [drm]] Modeline 0:"" 0 92450 1920 1968 2000 2080 1080 1083 1088 1111 0x0 0x9 oct. 18 16:27:24 NovHak-P2 kernel: [drm:intel_dump_pipe_config [i915]] adjusted mode: oct. 18 16:27:24 NovHak-P2 kernel: [drm:drm_mode_debug_printmodeline [drm]] Modeline 0:"1920x1080" 60 140490 1920 1972 2007 2094 1080 1083 1089 1118 0x48 0x9 I managed to have 40Hz through EDID modification, swapping the two DTDs it contains, one being 60Hz, the other 40Hz, hence placing the 40Hz DTD first, but then it remains sticked to 40Hz and unable to switch to a 60Hz mode. I suppose the bug is i915-related rather than Xorg-related, since the modelines seem correctly sent for KMS. I can provide additional information if needed. ProblemType: Bug DistroRelease: Ubuntu 19.04 Package: linux-image-generic 5.0.0.32.33 ProcVersionSignature: Ubuntu 5.0.0-32.34-generic 5.0.21 Uname: Linux 5.0.0-32-generic x86_64 ApportVersion: 2.20.10-0ubuntu27.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC2: olivier 12097 F.... pulseaudio /dev/snd/controlC0: olivier 12097 F.... pulseaudio /dev/snd/controlC1: olivier 12097 F.... pulseaudio CurrentDesktop: ubuntu:GNOME Date: Fri Oct 18 16:43:01 2019 InstallationDate: Installed on 2019-09-22 (26 days ago) InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416) MachineType: Notebook P17SM-A ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=fr_FR.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.0.0-32-generic root=UUID=788f8a5e-9667-4cfb-abf4-bc76ebcb86bb ro quiet splash mtrr_spare_reg_nr=0 vt.handoff=1 RelatedPackageVersions: linux-restricted-modules-5.0.0-32-generic N/A linux-backports-modules-5.0.0-32-generic N/A linux-firmware 1.178.3 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 03/27/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 4.6.5 dmi.board.asset.tag: Tag 12345 dmi.board.name: P17SM-A dmi.board.vendor: Notebook dmi.board.version: Not Applicable dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: To Be Filled By O.E.M. dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr4.6.5:bd03/27/2014:svnNotebook:pnP17SM-A:pvrNotApplicable:rvnNotebook:rnP17SM-A:rvrNotApplicable:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.: dmi.product.family: Not Applicable dmi.product.name: P17SM-A dmi.product.sku: Not Applicable dmi.product.version: Not Applicable dmi.sys.vendor: Notebook To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1848746/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
