I don't have a 4K monitor, but the following steps fixed video tearing with Kubuntu 16.04 on my Intel i7-2600k CPU with integrated Intel HD 3000 Graphics.
Edit /etc/environment and add the following lines: __GL_YIELD="USLEEP" KWIN_TRIPLE_BUFFER=0 KWIN_USE_BUFFER_AGE=0 Save the file and reboot. See the following link: Screen Tearing on Kubuntu 16.04 with Intel Drivers? https://askubuntu.com/questions/764302/screen-tearing-on-kubuntu-16-04-with-intel-drivers/774788 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1535447 Title: Intel Graphics 4K Screen Tearing Status in xorg package in Ubuntu: Expired Bug description: On a fresh boot all works well, but after an indeterminate amount of time the screen starts tearing badly, most noticeably as a permanent vertical tear. Once this tearing starts, it affects everything (desktop, etc) but is mostly visible in videos. The only way to get rid of the tear is to reboot. I do not know where this tearing is occurring, compositor? graphics driver? Hardware, Intel NUC5i5RYK (integrated graphics), LG 31MU97 DCI 4K monitor (4096x2160). Using a Mini DisplayPort to HDMI cable between the NUC and monitor. 00:02.0 VGA compatible controller: Intel Corporation Broadwell-U Integrated Graphics (rev 09) Software, Kubuntu 15.04 I also see the same problem in 15.10, but the computer I took the video of has 15.04 installed. The screen resolution is set to 4096x2160. In my syslog, I also see tons of these error messages (I dont know if they are related to the tearing). The error message repeats multiple times, and then stops. [ 668.879288] [drm:gen8_irq_handler [i915_bpo]] *ERROR* The master control interrupt lied (SDE)! I am hoping I can attach a video to this file which shows the tearing (5.7MB) --- ApportVersion: 2.17.2-0ubuntu1.8 Architecture: amd64 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: None CurrentDesktop: KDE DistUpgraded: Fresh install DistroCodename: vivid DistroRelease: Ubuntu 15.04 DistroVariant: kubuntu DkmsStatus: virtualbox, 4.3.34, 3.19.0-43-generic, x86_64: installed virtualbox, 4.3.34, 3.19.0-47-generic, x86_64: installed ExtraDebuggingInterest: No GraphicsCard: Intel Corporation Broadwell-U Integrated Graphics [8086:1626] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Intel Corporation Device [8086:2057] InstallationDate: Installed on 2016-01-12 (13 days ago) InstallationMedia: Kubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422) Package: xorg 1:7.7+7ubuntu4 PackageArchitecture: amd64 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-47-generic.efi.signed root=UUID=cfabd4b7-56e6-40a7-a43a-315a7389748e ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 3.19.0-47.53-generic 3.19.8-ckt10 Tags: third-party-packages vivid kubuntu UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev' Uname: Linux 3.19.0-47-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 12/22/2015 dmi.bios.vendor: Intel Corporation dmi.bios.version: RYBDWi35.86A.0353.2015.1222.0947 dmi.board.name: NUC5i5RYB dmi.board.vendor: Intel Corporation dmi.board.version: H40999-502 dmi.chassis.type: 3 dmi.modalias: dmi:bvnIntelCorporation:bvrRYBDWi35.86A.0353.2015.1222.0947:bd12/22/2015:svn:pn:pvr:rvnIntelCorporation:rnNUC5i5RYB:rvrH40999-502:cvn:ct3:cvr: version.compiz: compiz N/A version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.60-2 version.libgl1-mesa-dri: libgl1-mesa-dri 10.6.0-~0intel1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.6.0-~0intel1 version.xserver-xorg-core: xserver-xorg-core 2:1.17.1-0ubuntu3.1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.0-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.5.0-1ubuntu2 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917-1~exp1ubuntu2.3 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2build1 xserver.bootTime: Tue Jan 26 08:36:27 2016 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 38 vendor AJA xserver.version: 2:1.17.1-0ubuntu3.1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1535447/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
