For me, 4.4.0-78 actually made it worse on my Dell Latitude E7250 to the point where I had to downgrade to 4.4.0-72 in order to be able to use external monitors again.
With versions prior to 4.4.0-78, running xrandr a couple of times would usually cycle through all kinds of weird broken setups with parts of what was supposed to be shown on one monitor being shown in the corner of a different monitor and similar problems. But after a few attempts, it used to somehow "get it right" and display the right layout. With 4.4.0-78, this workaround stopped working as even though the layout may be correct, there simply is "no signal" on external monitors. They are detected by xrandr as being present and connected, the window manager appears to recognize them but neither of them receives a video signal so they just go to sleep after a few seconds. The built-in notebook display keeps working all the time. External monitors appear to work up to the point at which the switch from "VESA VGA" to "inteldrmfb" occurs. After going back to 4.4.0-72, all issues went away. Even the layout options given to xrandr now work as expected. I looks like something is horribly wrong with Intel graphics support. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1686189 Title: External monitor connecting problem on Intel graphics card Status in linux package in Ubuntu: Confirmed Status in xorg package in Ubuntu: Confirmed Bug description: I am facing a problem with Intel Graphics driver. I have external monitor and in display settings the second monitor is detecting but it's not working, so could you email me a solution. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: xorg 1:7.7+13ubuntu3 Uname: Linux 4.4.25-040425-generic x86_64 .tmp.unity_support_test.0: ApportVersion: 2.20.1-0ubuntu2.5 Architecture: amd64 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Tue Apr 25 21:45:16 2017 DistUpgraded: 2017-04-25 21:07:40,819 DEBUG icon theme changed, re-reading DistroCodename: xenial DistroVariant: ubuntu DkmsStatus: i915-4.6.3-4.4.0, 1, 4.4.0-75-generic, x86_64: installed GraphicsCard: Intel Corporation Haswell-ULT Integrated Graphics Controller [8086:0a16] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Dell Haswell-ULT Integrated Graphics Controller [1028:05e9] InstallationDate: Installed on 2017-04-25 (0 days ago) InstallationMedia: Ubuntu 14.04.5 LTS "Trusty Tahr" - Release amd64 (20160803) MachineType: Dell Inc. Inspiron 3537 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.25-040425-generic root=UUID=3914e6d5-5c87-4816-8043-776ef4184d29 ro quiet splash vt.handoff=7 SourcePackage: xorg UpgradeStatus: Upgraded to xenial on 2017-04-25 (0 days ago) dmi.bios.date: 04/30/2014 dmi.bios.vendor: Dell Inc. dmi.bios.version: A08 dmi.board.name: 03JPPR dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: A08 dmi.modalias: dmi:bvnDellInc.:bvrA08:bd04/30/2014:svnDellInc.:pnInspiron3537:pvrA08:rvnDellInc.:rn03JPPR:rvrA00:cvnDellInc.:ct8:cvrA08: dmi.product.name: Inspiron 3537 dmi.product.version: A08 dmi.sys.vendor: Dell Inc. version.compiz: compiz 1:0.9.12.2+16.04.20160823-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.70-1~ubuntu16.04.1 version.libgl1-mesa-dri: libgl1-mesa-dri 12.0.6-0ubuntu0.16.04.1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 12.0.6-0ubuntu0.16.04.1 version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-0ubuntu0.2 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1.2 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2 xserver.bootTime: Tue Apr 25 21:37:24 2017 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 17900 vendor AUO xserver.version: 2:1.18.4-0ubuntu0.2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1686189/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
