Changing resolution on session make desktop unusable

[asu]

$ uname -a
Linux 192-168-0-3 3.19.0-16-generic #16-Ubuntu SMP Thu Apr 30 16:13:00 UTC 2015 i686 i686 i686 GNU/Linux
$ lspci
00:00.0 Host bridge: Intel Corporation 82945G/GZ/P/PL Memory Controller Hub (rev 02)
00:02.0 VGA compatible controller: Intel Corporation 82945G/GZ Integrated Graphics Controller (rev 02)
00:1b.0 Audio device: Intel Corporation NM10/ICH7 Family High Definition Audio Controller (rev 01)
00:1c.0 PCI bridge: Intel Corporation NM10/ICH7 Family PCI Express Port 1 (rev 01)
00:1d.0 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #1 (rev 01)
00:1d.1 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #2 (rev 01)
00:1d.2 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #3 (rev 01)
00:1d.3 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #4 (rev 01)
00:1d.7 USB controller: Intel Corporation NM10/ICH7 Family USB2 EHCI Controller (rev 01)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev e1)
00:1f.0 ISA bridge: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface Bridge (rev 01)
00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller (rev 01)
00:1f.2 IDE interface: Intel Corporation NM10/ICH7 Family SATA Controller [IDE mode] (rev 01)
00:1f.3 SMBus: Intel Corporation NM10/ICH7 Family SMBus Controller (rev 01)
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 02)
$ dpkg -s unity
Package: unity
Status: install ok installed
Priority: optional
Section: gnome
Installed-Size: 6736
Maintainer: Ubuntu Developers <email address hidden>
Architecture: i386
Version: 7.3.2+15.04.20150420-0ubuntu1
Provides: indicator-renderer
Depends: compiz-core, libatk-bridge2.0-0 (>= 2.5.3), libatk1.0-0 (>= 2.2.0), libbamf3-2 (>= 0.5.0), libc6 (>= 2.17), libcairo2 (>= 1.14.0), libdbusmenu-glib4 (>= 0.4.2), libdee-1.0-4 (>= 0.5.2), libgcc1 (>= 1:4.1.1), libgdk-pixbuf2.0-0 (>= 2.22.0), libgl1-mesa-glx | libgl1, libglew1.10 (>= 1.10.0), libglib2.0-0 (>= 2.41.1), libgnome-desktop-3-10 (>= 3.11.90), libgtk-3-0 (>= 3.11.5), libindicator3-7 (>= 0.4.90), libjson-glib-1.0-0 (>= 0.12.0), libnotify4 (>= 0.7.0), libnux-4.0-0, libpam0g (>= 0.99.7.1), libpango-1.0-0 (>= 1.22.0), libpangocairo-1.0-0 (>= 1.14.0), libsigc++-2.0-0c2a (>= 2.2.0), libstdc++6 (>= 4.9), libunity-core-6.0-9 (= 7.3.2+15.04.20150420-0ubuntu1), libunity-misc4 (>= 4.0.2), libunity-protocol-private0 (>= 7.1.4+14.10.20140808), libx11-6 (>= 2:1.2.99.901), libxext6, libxfixes3 (>= 1:5.0.1-1), libxi6 (>= 2:1.7.1.901), libxrender1, libzeitgeist-2.0-0 (>= 0.9.9), session-migration, python:any, compiz, compiz-core-abiversion-20140123, libnux-abiversion-20140307.0, compiz-plugins-default, libglib2.0-bin, nux-tools, python3-gi, dconf-cli, unity-asset-pool (>= 0.8.18), unity-greeter, bamfdaemon, unity-scope-home
Recommends: unity-control-center, unity-scope-virtualbox, unity-scope-chromiumbookmarks, unity-lens-applications, unity-scope-zotero, unity-scope-clementine, unity-lens-files, unity-scope-devhelp, unity-scope-colourlovers, unity-scope-gourmet, unity-scope-firefoxbookmarks, unity-scope-audacious, unity-scope-texdoc, unity-scope-video-remote, unity-scope-manpages, unity-scope-tomboy, unity-scope-guayadeque, unity-scope-musicstores, unity-lens-music, unity-scope-yelp, unity-scope-calculator, unity-lens-photos, unity-scope-openclipart, unity-scope-musique, unity-scope-gmusicbrowser, unity-scope-gdrive, unity-lens-video, indicator-appmenu (>= 15.02.0), indicator-application, indicator-sound, indicator-bluetooth, indicator-datetime, indicator-keyboard, indicator-messages, indicator-printers, indicator-power, indicator-session, telepathy-indicator, hud
Breaks: unity-lens-applications (<< 5.12.0-0ubuntu2), unity-lens-files (<< 5.10.0-0ubuntu2), unity-lens-music (<< 6.0.0), unity-lens-video (<< 0.3.6-0ubuntu2)
Conffiles:
 /etc/pam.d/unity 6db13401571f575bd03b96a501817be7
Description: Interface designed for efficiency of space and interaction.
 Unity is a desktop experience that sings. Designed by Canonical and the Ayatana
 community, Unity is all about the combination of familiarity and the future. We
 bring together visual design, analysis of user experience testing, modern
 graphics technologies and a deep understanding of the free software landscape
 to produce what we hope will be the lightest, most elegant and most delightful
 way to use your PC.
Homepage: https://launchpad.net/unity

$ xrandr
Screen 0: minimum 8 x 8, current 1280 x 1024, maximum 32767 x 32767
VGA1 connected primary 1280x1024+0+0 (normal left inverted right x axis y axis) 473mm x 296mm
   1680x1050 59.9 +
   1280x1024 75.0 60.0*
   1440x900 75.0 59.9
   1024x768 75.1 70.1 60.0
   800x600 72.2 75.0 60.3 56.2
   640x480 75.0 72.8 60.0
   720x400 70.1
VIRTUAL1 disconnected (normal left inverted right x axis y axis)

$ lsmod | grep video
video 20480 1 i915

$ Xorg -version

X.Org X Server 1.17.1
Release Date: 2015-02-10
X Protocol Version 11, Revision 0
Build Operating System: Linux 3.2.0-76-generic i686 Ubuntu
Current Operating System: Linux 192-168-0-3 3.19.0-16-generic #16-Ubuntu SMP Thu Apr 30 16:13:00 UTC 2015 i686
Kernel command line: BOOT_IMAGE=/vmlinuz-3.19.0-16-generic root=/dev/mapper/192--168--0--102--vg-root ro splash quiet libata.dma=0 vt.handoff=7
Build Date: 19 March 2015 09:27:07AM
xorg-server 2:1.17.1-0ubuntu3 (For technical support please see http://www.ubuntu.com/support)
Current version of pixman: 0.32.6
 Before reporting problems, check http://wiki.x.org
 to make sure that you have the latest version.

$ compiz --version
Compiz 0.9.12.1

How reproduce this bug:
My desktop resol current resol is 1280x1024 and want to change on 1024x768
On Unity session run
xrandr --output VGA1 --mode 1024x768
Result : sreen is unusable and must restart system to bee ok

[asu (corcodel-marian)]

From CompizConfig Settings Manager ->Advanced Search->OpenGL->Texture Compression set disable and alls in ok.
This setting is very dangerous and break the desktop on my case.