Hi All I have been following this, having been led here by the guys from Ubuntu Budgie.
My GFX card is a Mesa DRI Intel UHD Graphics 620 (Kabylake GT2) v: 4.5 Mesa 19.0.8 At 18.10 kernel all is fine with both flickering gone and being able to join screens via VGA / HDMI At 19.04 this is not the case with flickering occurring when the VGA cable is removed and built in screen of laptop is standalone. Have downloaded and applied various other kernels from https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-intel- nightly/current/ and have found that all work in some form of either curing the flicker but no ext VGA to having both, but no settings options in display settings from the desktop. Kernel 5.3.0-994 on the above URL however does work, with display settings and ext VGA / HDMI and standalone built in screen, with all function keys working too. Appreciate this is some leap from the supplied 5.0.0.27 kernel that came with my distro, but if people are in a position be able to load this kernel and choose at boot time then it might be fixed for you too. How you determine what is different between the kernels to see why it works now is another matter. -- 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/1785912 Title: Horizontal screen flicker Intel UHD graphics 620 (rev 07) Lenovo Ideapad 720s 13IKB 81BV Status in Linux: Confirmed Status in linux package in Ubuntu: Incomplete Bug description: Horrible screen flicker from login screen and after login. 18.04.1 LTS. I have two similar laptops, both Lenovo Ideapad 720s 13IKB, model 81A8 - Core i5 7200U - Intel HD Graphics 620 Rev 02 - works fine. model 81BV - Core i5 8250U - Intel UHD Graphics 620 Rev 07 - awful screen flashing. Neither have the problem in Windows (ie hardware fine) I installed the standard Ubuntu 18.04 on each of them (same USB Key, few weeks apart) but only the 81BV / 8th gen / UHD 620 Rev 07 has the problem. Flickering visible on video here: https://photos.app.goo.gl/HCN73q1nQfgstgVBA I've used ubuntu-bug so I believe you have all the details of the machine. The install came straight from your standard 18.04 download. Any changes are due to me trying to fix this (not much prev exp of kernel params etc) Things tried but which didn't work were: - enable huc/guc (got it to load - it's now visible in the attached dmesg - but didn't help.) - enable_rc6=0 (just stopped sleep / resume working) - edp_vswing=2 ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: xserver-xorg-video-intel 2:2.99.917+git20171229-1 ProcVersionSignature: Ubuntu 4.15.0-30.32-generic 4.15.18 Uname: Linux 4.15.0-30-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.2 Architecture: amd64 CompositorRunning: None Date: Tue Aug 7 23:09:14 2018 DistUpgraded: Fresh install DistroCodename: bionic DistroVariant: ubuntu ExtraDebuggingInterest: Yes, if not too technical GraphicsCard: Intel Corporation UHD Graphics 620 [8086:5917] (rev 07) (prog-if 00 [VGA controller]) Subsystem: Lenovo UHD Graphics 620 [17aa:39af] InstallationDate: Installed on 2018-08-06 (1 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) Lsusb: Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 004: ID 0cf3:e500 Atheros Communications, Inc. Bus 001 Device 003: ID 5986:210d Acer, Inc Bus 001 Device 002: ID 06cb:0081 Synaptics, Inc. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub MachineType: LENOVO 81BV ProcEnviron: TERM=xterm-256color PATH=(custom, no user) LANG=en_GB.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-30-generic root=UUID=10eb4e00-26e4-4f42-b983-9a603a658f89 ro i915.enable_guc=3 i915.enable_guc_loading=1 SourcePackage: xserver-xorg-video-intel UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 05/02/2018 dmi.bios.vendor: LENOVO dmi.bios.version: 6MCN27WW dmi.board.asset.tag: NO Asset Tag dmi.board.name: LNVNB161216 dmi.board.vendor: LENOVO dmi.board.version: SDK0J40709 WIN dmi.chassis.asset.tag: NO Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Lenovo ideapad 720S-13IKB dmi.modalias: dmi:bvnLENOVO:bvr6MCN27WW:bd05/02/2018:svnLENOVO:pn81BV:pvrLenovoideapad720S-13IKB:rvnLENOVO:rnLNVNB161216:rvrSDK0J40709WIN:cvnLENOVO:ct10:cvrLenovoideapad720S-13IKB: dmi.product.family: ideapad 720S-13IKB dmi.product.name: 81BV dmi.product.version: Lenovo ideapad 720S-13IKB dmi.sys.vendor: LENOVO version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.91-2 version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.5-0ubuntu0~18.04.1 version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.5-0ubuntu0~18.04.1 version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2 To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1785912/+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
