Hi, I updated the bios. The problem still remains, but the occurence time has reduced.
Now I have the problem only once a day. If can be usefull, please consider that the problem does not appear inside external applications windows. For example, VirtualBox sessions are not affected by the issue. Here is the output of the command " sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date" V1.07 08/10/2012 ** Changed in: xorg (Ubuntu) Status: Incomplete => Confirmed -- 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/1458663 Title: Characters disappear and graphic major problems Status in xorg package in Ubuntu: Confirmed Bug description: After some minuter working, the characters on screen start to disappera or to be bad rendered. Also other glitches appear on screen. Only solution is to reboot. ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: xorg 1:7.7+7ubuntu4 ProcVersionSignature: Ubuntu 3.19.0-18.18-generic 3.19.6 Uname: Linux 3.19.0-18-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 2.17.2-0ubuntu1.1 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: Mon May 25 21:49:34 2015 DistUpgraded: Fresh install DistroCodename: vivid DistroVariant: ubuntu DkmsStatus: vboxhost, 4.3.28, 3.19.0-16-generic, x86_64: installed vboxhost, 4.3.28, 3.19.0-18-generic, x86_64: installed ExtraDebuggingInterest: Yes, including running git bisection searches GraphicsCard: Intel Corporation Core Processor Integrated Graphics Controller [8086:0046] (rev 02) (prog-if 00 [VGA controller]) Subsystem: Acer Incorporated [ALI] Device [1025:0612] InstallationDate: Installed on 2015-05-13 (11 days ago) InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422) Lsusb: Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 0402:7675 ALi Corp. Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub MachineType: Acer TravelMate 5744 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-18-generic root=UUID=a47868a6-c53a-4f67-b654-d6f1056a0cc5 ro quiet splash vt.handoff=7 SourcePackage: xorg UdevLog: Error: [Errno 2] File o directory non esistente: '/var/log/udev' UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/27/2011 dmi.bios.vendor: Insyde Corp. dmi.bios.version: V1.04 dmi.board.asset.tag: Type2 - Board Asset Tag dmi.board.name: BA52_CP dmi.board.vendor: Acer dmi.board.version: Type2 - Board Version dmi.chassis.type: 10 dmi.chassis.vendor: Chassis Manufacturer dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.04:bd07/27/2011:svnAcer:pnTravelMate5744:pvrV1.04:rvnAcer:rnBA52_CP:rvrType2-BoardVersion:cvnChassisManufacturer:ct10:cvrChassisVersion: dmi.product.name: TravelMate 5744 dmi.product.version: V1.04 dmi.sys.vendor: Acer version.compiz: compiz 1:0.9.12.1+15.04.20150410.1-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.60-2 version.libgl1-mesa-dri: libgl1-mesa-dri 10.5.2-0ubuntu1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.5.2-0ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.17.1-0ubuntu3 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~exp1ubuntu2.1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2build1 xserver.bootTime: Mon May 25 21:42:49 2015 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: xserver.version: 2:1.17.1-0ubuntu3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1458663/+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