Was affected by the same issue. Managed to fix it by selecting "Use graphics processor for scaling" on the affected display (under the "Adjustments" tab) in Catalyst Control Centre.
-- 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/1311881 Title: dual screen ubuntu 14.04, second screen only partially displaying desktop Status in “xorg” package in Ubuntu: Confirmed Bug description: The second screen on my 2 monitor Ubuntu 14.04 setup is only partially showing any of the desktop. The primary screen is a 22" 1680*1050 and the secondary screen is 1920*1200. The primary screen has a complete and true 1680*1050 desktop, but the secondary screen only shows 1" of the 1920*1200 screen down the left vertical. The rest of the desktop is obscured under some "black window", with only the mouse being displayed as it travels through that screen. Any windows or items below that black area, can be interacted with, and the mouse indicates their presence with resize/minimise and other hints, but they do not display over the black area. The system was working perfectly fine in 13.10 and this issue only occurred after I upgraded to 14.04 and, faced with a "failed to start session" bug on the login screen, resorted to an "apt-get install ubuntu-desktop" to get my desktop up and running. My graphics card is an ATI Radeon HD 6670 and my monitors are Samsung Syncmaster 2232bw (22") and Dell UM2412M. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: xorg 1:7.7+1ubuntu8 ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9 Uname: Linux 3.13.0-24-generic x86_64 NonfreeKernelModules: fglrx .tmp.unity.support.test.0: ApportVersion: 2.14.1-0ubuntu3 Architecture: amd64 CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell] CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Wed Apr 23 21:51:03 2014 DistUpgraded: 2014-04-23 18:43:48,762 DEBUG enabling apt cron job DistroCodename: trusty DistroVariant: ubuntu ExtraDebuggingInterest: Yes, if not too technical GraphicsCard: Advanced Micro Devices, Inc. [AMD/ATI] Turks XT [Radeon HD 6670/7670] [1002:6758] (prog-if 00 [VGA controller]) Subsystem: ASUSTeK Computer Inc. Device [1043:0443] InstallationDate: Installed on 2012-09-24 (576 days ago) InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1) MachineType: System manufacturer System Product Name ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-24-generic root=UUID=1aff935b-13e8-475e-a845-3d816a582db2 ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to trusty on 2014-04-23 (0 days ago) dmi.bios.date: 03/23/2012 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 1103 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: M5A78L-M/USB3 dmi.board.vendor: ASUSTeK Computer INC. dmi.board.version: Rev X.0x dmi.chassis.asset.tag: Asset-1234567890 dmi.chassis.type: 3 dmi.chassis.vendor: Chassis Manufacture dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1103:bd03/23/2012:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnM5A78L-M/USB3:rvrRevX.0x:cvnChassisManufacture:ct3:cvrChassisVersion: dmi.product.name: System Product Name dmi.product.version: System Version dmi.sys.vendor: System manufacturer version.compiz: compiz 1:0.9.11+14.04.20140409-0ubuntu1 version.fglrx-installer: fglrx-installer N/A version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.52-1 version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0-4ubuntu5 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0-4ubuntu5 version.xserver-xorg-core: xserver-xorg-core 2:1.15.1-0ubuntu2 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2 xserver.bootTime: Wed Apr 23 22:38:29 2014 xserver.configfile: default xserver.errors: open /dev/dri/card0: No such file or directory AIGLX error: failed to open /usr/X11R6/lib64/modules/dri/fglrx_dri.so, error[/usr/X11R6/lib64/modules/dri/fglrx_dri.so: cannot open shared object file: No such file or directory] AIGLX error: failed to open /usr/lib64/dri/fglrx_dri.so, error[/usr/lib64/dri/fglrx_dri.so: cannot open shared object file: No such file or directory] AIGLX error: failed to open /usr/X11R6/lib/modules/dri/fglrx_dri.so, error[/usr/X11R6/lib/modules/dri/fglrx_dri.so: cannot open shared object file: No such file or directory] xserver.logfile: /var/log/Xorg.0.log xserver.version: 2:1.15.1-0ubuntu2 xserver.video_driver: fglrx To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1311881/+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