https://bugs.freedesktop.org/show_bug.cgi?id=27644
Summary: radeon KMS causes corrupt VGA output on X1400 Product: DRI Version: unspecified Platform: x86 (IA32) OS/Version: Linux (All) Status: NEW Severity: normal Priority: medium Component: DRM/Radeon AssignedTo: dri-devel@lists.freedesktop.org ReportedBy: sastraxi@gmail.com
(note first that this is connected to an Ubuntu bug report; take a look for some potentially-helpful logs: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/562138)
Booting up the latest 10.04 daily live-cd of Ubuntu, the VGA output is unusable. It looks like an incorrect frequency, and the screen size is wrong (it's too narrow for the resolution). The wavering/out-of-phase-ness is so bad that it's impossible to read. This happens on both the X console and X11, and goes away when I use the internal laptop LCD instead (LVDS). If I use both screens in a mirror or extend mode, the same problems occur. So, this led me to believe that the problem might be with Kernel Mode Setting (KMS).
I added the options: "radeon.modeset=0 vga=771" to the livecd and, voila, no more corruption. Everything works again, and I can use my big LCD via VGA!
I've attached as much information as I can; I can also show a video of the corruption. I had Ubuntu 8.10 on my computer previously; it's a Dell Inspiron 6400 with Mobility X1400 graphics from ati. I'm using the April 13th Daily LiveCD here, but the corruption was evident at least with the latest Beta livecd.
Let me know if I can give any more information!
ProblemType: Bug DistroRelease: Ubuntu 10.04 Package: xorg 1:7.5+5ubuntu1 ProcVersionSignature: Ubuntu 2.6.32-20.30-generic 2.6.32.11+drm33.2 Uname: Linux 2.6.32-20-generic i686 Architecture: i386 Date: Tue Apr 13 04:48:04 2010 LiveMediaBuild: Ubuntu 10.04 "Lucid Lynx" - Alpha i386 (20100413) MachineType: Dell Inc. MM061 ProcCmdLine: initrd=/ubninit file=/cdrom/preseed/hostname.seed boot=casper quiet radeon.modeset=0 vga=771 BOOT_IMAGE=/ubnkern ProcEnviron: LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: xorg Symptom: display dmi.bios.date: 04/20/2007 dmi.bios.vendor: Dell Inc. dmi.bios.version: A15 dmi.board.name: 0XD720 dmi.board.vendor: Dell Inc. dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvrA15:bd04/20/2007:svnDellInc.:pnMM061:pvr:rvnDellInc.:rn0XD720:rvr:cvnDellInc.:ct8:cvr: dmi.product.name: MM061 dmi.sys.vendor: Dell Inc. system: distro: Ubuntu codename: lucid architecture: i686 kernel: 2.6.32-20-generic