12.04 does not allow multiple monitor setup

[hackvan]

Unity 3D supported: [31;01mno[00m

on hardware that worked fine with 11.10, ubuntu 12.04 beta2 is now failing to use the second screen on my old notebook as a second display. it seems to be related to unity's 3d demands (which, quite honestly I wish I could completely un-install as they just eat up reasources that I don't want to spend on unnecessary graphics whizziness)...

So, here's the chain of failures that I see...

at initial login screen, there's a complaint about not being able to use the second monitor because the 3d virtual desktop cannot exceed 2048x2048

login menu doesn't seem to register my choice for unity 2d.

logged in, i can't un-clone the built-in display and the external 15" panel because, again, the gnome settings apparatus is complaining about illegal display offsets.

.... and * I DON'T EVEN WANT 3D !!!!
.... the defaults should force everything to 2d if the hardware doesn't support accelleration at the resolution you have.
.... performance is more important than prettiness... unity 2d should be the default if there's only software 3d.

ProblemType: BugDistroRelease: Ubuntu 12.04
Package: xorg 1:7.6+12ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
.tmp.unity.support.test.1:

ApportVersion: 2.0.1-0ubuntu4
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
Date: Mon Apr 16 11:48:06 2012
DistUpgraded: Fresh install
DistroCodename: precise
DistroVariant: ubuntu
GraphicsCard:
 Advanced Micro Devices [AMD] nee ATI RS482 [Radeon Xpress 200M] [1002:5975] (prog-if 00 [VGA controller])
   Subsystem: Gateway 2000 Device [107b:0367]
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120328)
MachineType: Gateway MT6452
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-23-generic root=UUID=f4c06577-5df4-44fe-bde5-464c30aab825 ro recovery nomodeset
Renderer: SoftwareSourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/01/2006
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: 84.05
dmi.board.vendor: Gateway
dmi.board.version: 84.05
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 8
dmi.chassis.vendor: Gateway
dmi.chassis.version: Rev.1
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvr84.05:bd11/01/2006:svnGateway:pnMT6452:pvr3408447R:rvnGateway:rn:rvr84.05:cvnGateway:ct8:cvrRev.1:
dmi.product.name: MT6452
dmi.product.version: 3408447R
dmi.sys.vendor: Gateway
version.compiz: compiz 1:0.9.7.6-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.2-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.2-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu10
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2

[Sebastien Bacher (seb128)]

Seems like a limitation of the ati driver you might want to try to use fglrx rather

[Sebastien Bacher (seb128)]

Closing the Unity part, the bottom of the issue is that fglrx fails to load (seeing Xorg.0.log) and that the ati driver has this screen size limitation. The "can't select 2d" would be a lightdm issue and should open a new bug about it if that's still happening

[hackvan (stig-launchpad)]

I'm not sure what changed, but un-mirrored displays are now working on my old notebook.

I'm not entirely sure what made the change.

[madbiologist (me-again)]

This fix sounds related to the R300CheckComposite function in the xf86-video-ati (xserver-xorg-video-ati) driver. The ATI RS482 [Radeon Xpress 200M] is based on the Radeon X300 (RV370) chip. It has also recently been found that some RS6xx seem to have R3xx limitations as far as clipping is concerned. See https://bugs.freedesktop.org/show_bug.cgi?id=58469 for more info.

[madbiologist (me-again)]

Forget what I wrote. According to https://launchpad.net/ubuntu/+source/xserver-xorg-video-ati that driver has not been updated between your bug report and now.

Anyway, it's fixed, so marking as Fix Released.