Could you, please, help me with this "solution #8 ? I don't know what it is. Which is the "config file" you referrer to?Thanks.

> Date: Sun, 15 Nov 2015 20:44:34 +0000
> From: <email address hidden>
> To: <email address hidden>
> Subject: [Bug 1507255] Re: Garbled graphics in Wily with Intel GMA4500 chip
> 
> Solution in #8 worked for me as well. Upgraded to 15.10 and had the
> garbled screen. The config file fixed it.
> 
> -- 
> You received this bug notification because you are subscribed to a
> duplicate bug report (1509196).
> https://bugs.launchpad.net/bugs/1507255
> 
> Title:
>   Garbled graphics in Wily with Intel GMA4500 chip
> 
> Status in xserver-xorg-video-intel package in Ubuntu:
>   Confirmed
> 
> Bug description:
>   This affects both Ubuntu GNOME and Ubuntu Wily 20151017.1. The
>   graphics are so badly garbled I can only file this bug on an
>   unaffected OS where I've held back the update on just that one package
>   to about Beta 1 status:
> 
>   lance@lance-INTEL-desktop:~$ apt-cache policy xserver-xorg-video-intel
>   xserver-xorg-video-intel:
>     Installed: 2:2.99.917-1ubuntu1
>     Candidate: 2:2.99.917+git20150808-0ubuntu4
>     Version table:
>        2:2.99.917+git20150808-0ubuntu4 0
>           500 http://us.archive.ubuntu.com/ubuntu/ wily/main i386 Packages
>    *** 2:2.99.917-1ubuntu1 0
>           100 /var/lib/dpkg/status
> 
>   I'll attach a picture of the garbled screen with the updated xserver-
>   xorg-video-intel package. Oddly a screenshot taken from the affected
>   OS displays perfectly OK in the unaffected OS so I used my camera.
> 
>   The info provided by lspci may not be very helpful:
> 
>   lance@lance-INTEL-desktop:~$ lspci -v -s `lspci | awk '/VGA/{print $1}'`
>   00:02.0 VGA compatible controller: Intel Corporation 4 Series Chipset Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
>    Subsystem: Intel Corporation Device 0025
>    Flags: bus master, fast devsel, latency 0, IRQ 27
>    Memory at d0000000 (64-bit, non-prefetchable) [size=4M]
>    Memory at c0000000 (64-bit, prefetchable) [size=256M]
>    I/O ports at f1c0 [size=8]
>    Expansion ROM at <unassigned> [disabled]
>    Capabilities: <access denied>
>    Kernel driver in use: i915
> 
>   The tech specs show:
> 
>   Internal Graphics:
>   • Intel ® GMA4500 onboard graphics subsystem with support for:
>   ― Analog displays (VGA)
>   ― Digital displays (DVI-D)
> 
>   I'm just using VGA ATM.
> 
>   Something else worth mentioning is this warning displayed while filing
>   the bug report:
> 
>   Your system is providing 3D via software rendering rather than
>   hardware rendering.  This is a compatibility mode which should display
>   3D graphics properly but the performance may be very poor.  If the
>   problem you're reporting is related to graphics performance, your real
>   question may be why X didn't use hardware acceleration for your
>   system.
> 
>   I did try booting an earlier kernel to no avail, but holding back just
>   this one update prevents the borkage.
> 
>   ProblemType: Bug
>   DistroRelease: Ubuntu 15.10
>   Package: xserver-xorg-video-intel 2:2.99.917-1ubuntu1
>   ProcVersionSignature: Ubuntu 4.2.0-16.19-generic 4.2.3
>   Uname: Linux 4.2.0-16-generic i686
>   ApportVersion: 2.19.1-0ubuntu2
>   Architecture: i386
>   CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
>   CompositorRunning: None
>   CurrentDesktop: GNOME
>   Date: Sun Oct 18 00:17:35 2015
>   DistUpgraded: Fresh install
>   DistroCodename: wily
>   DistroVariant: ubuntu
>   ExtraDebuggingInterest: Yes, if not too technical
>   GraphicsCard:
>    Intel Corporation 4 Series Chipset Integrated Graphics Controller [8086:2e42] (rev 03) (prog-if 00 [VGA controller])
>      Subsystem: Intel Corporation Device [8086:0025]
>      Subsystem: Intel Corporation Device [8086:0025]
>   InstallationDate: Installed on 2015-08-26 (52 days ago)
>   InstallationMedia: Ubuntu-GNOME 15.10 "Wily Werewolf" - Alpha i386 (20150826.1)
>   ProcEnviron:
>    TERM=xterm-256color
>    PATH=(custom, no user)
>    XDG_RUNTIME_DIR=<set>
>    LANG=en_US.UTF-8
>    SHELL=/bin/bash
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-16-generic root=UUID=39597a1e-90b6-4e81-ae29-4c01d28f7f17 ro quiet splash vt.handoff=7
>   Renderer: Software
>   SourcePackage: xserver-xorg-video-intel
>   UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
>   UpgradeStatus: No upgrade log present (probably fresh install)
>   dmi.bios.date: 12/23/2010
>   dmi.bios.vendor: Intel Corp.
>   dmi.bios.version: LDB4310H.86A.0037.2010.1223.1121
>   dmi.board.asset.tag: To be filled by O.E.M.
>   dmi.board.name: DB43LD
>   dmi.board.vendor: Intel Corporation
>   dmi.board.version: AAE60577-202
>   dmi.chassis.type: 3
>   dmi.modalias: dmi:bvnIntelCorp.:bvrLDB4310H.86A.0037.2010.1223.1121:bd12/23/2010:svn:pn:pvr:rvnIntelCorporation:rnDB43LD:rvrAAE60577-202:cvn:ct3:cvr:
>   version.compiz: compiz N/A
>   version.libdrm2: libdrm2 2.4.64-1
>   version.libgl1-mesa-dri: libgl1-mesa-dri 11.0.2-1ubuntu4
>   version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
>   version.libgl1-mesa-glx: libgl1-mesa-glx 11.0.2-1ubuntu4
>   version.xserver-xorg-core: xserver-xorg-core 2:1.17.2-1ubuntu9
>   version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.2-1ubuntu1
>   version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.5.0+git20150819-0ubuntu1
>   version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917-1ubuntu1
>   version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu3
>   xserver.bootTime: Sat Oct 17 23:58:59 2015
>   xserver.configfile: default
>   xserver.errors:
>    AIGLX error: Calling driver entry point failed
>    AIGLX: reverting to software rendering
>   xserver.logfile: /var/log/Xorg.0.log
>   xserver.outputs:
> 
>   xserver.version: 2:1.17.2-1ubuntu9
> 
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