It just happens I can do this now... Am running kernel 3.5.0-030500rc7-generic now but it behaves just like the other kernels I have tried. Earlier today I raised a kernel bug report #44851 at bugzilla.kernel.org - pointing at suspend/resume, but I think its the same thing. I will do the documentation you specified.
** Tags added: kernel-bug-exists-upstream ** Description changed: - Running 12.10, updated today, on iMac 11,2 (mid 2010) with AMD Radeon 4670. - Using kernel radeon driver (lsmod shows it running). + Running 12.10, updated today, on iMac 11,2 (mid 2010) with AMD Radeon 4670. + Using kernel radeon driver (lsmod shows it running). Normal boot results in black screen. Ctl-Alt-Del reboots; indicating that system did boot. If I place 'nomodeset' on kernel command line, main screen can be seen and unity desktop runs normally. This appears to be a regression in the kernel, similar to bug 597070 (ubuntu 11.04 - used fglrx to get video to work) and to bug 863969 (ubuntu 11.10 - where an upgrade to the 3.2 kernel seemed to improve video detection). Suspend and resume does not work either, not turning off the system, only the video, and resuming to a black screen. I think the problem is in KMS, because the black screen happens even if I boot into text mode and using nomodeset fixes it. Hence filing this against xorg but expect it to go to kernel developers. ProblemType: Bug DistroRelease: Ubuntu 12.10 Package: xorg 1:7.7+1ubuntu1 ProcVersionSignature: Ubuntu 3.5.0-4.4-generic 3.5.0-rc6 Uname: Linux 3.5.0-4-generic x86_64 .tmp.unity.support.test.1: - + ApportVersion: 2.3-0ubuntu4 Architecture: amd64 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: None Date: Fri Jul 13 19:12:16 2012 DistUpgraded: Fresh install DistroCodename: quantal DistroVariant: ubuntu ExtraDebuggingInterest: Yes, GraphicsCard: - Advanced Micro Devices [AMD] nee ATI RV730 XT [Mobility Radeon HD 4670] [1002:9488] (prog-if 00 [VGA controller]) - Subsystem: Apple Inc. Device [106b:00b6] + Advanced Micro Devices [AMD] nee ATI RV730 XT [Mobility Radeon HD 4670] [1002:9488] (prog-if 00 [VGA controller]) + Subsystem: Apple Inc. Device [106b:00b6] InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64+mac (20120509) MachineType: Apple Inc. iMac11,2 ProcEnviron: - LANGUAGE=en_GB:en - TERM=xterm - PATH=(custom, no user) - LANG=en_GB.UTF-8 - SHELL=/bin/bash + LANGUAGE=en_GB:en + TERM=xterm + PATH=(custom, no user) + LANG=en_GB.UTF-8 + SHELL=/bin/bash ProcKernelCmdLine: vmlinuz-3.5.0-4-generic root=UUID=268e7eb7-d871-478c-a906-b719eea881ea ro nosplash nomodeset initrd=EFI\ubuntu\initrd.img-3.5.0-4-generic SourcePackage: xorg Symptom: display UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 12/09/11 dmi.bios.vendor: Apple Inc. dmi.bios.version: IM112.88Z.0057.B01.1112090906 dmi.board.name: Mac-F2238AC8 dmi.board.vendor: Apple Inc. dmi.chassis.type: 13 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-F2238AC8 dmi.modalias: dmi:bvnAppleInc.:bvrIM112.88Z.0057.B01.1112090906:bd12/09/11:svnAppleInc.:pniMac11,2:pvr1.0:rvnAppleInc.:rnMac-F2238AC8:rvr:cvnAppleInc.:ct13:cvrMac-F2238AC8: dmi.product.name: iMac11,2 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. version.compiz: compiz 1:0.9.8+bzr3249-0ubuntu2 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.33-3 version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.3-0ubuntu1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.3-0ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.12.1.902-1ubuntu1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.19.0-1ubuntu2 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.1-1build1 ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1024507 Title: 12.10 quantal boots to black screen on iMac To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1024507/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs