Using a Radeon HD 4650 with a LG W3000H screen, with either git drivers or the ones that come with the ubuntu lucid beta, results in a black screen on boot. When attaching a second screen and switching to a lower resolution the screen works, switching back up again gives a black screen. Since the card should be able to do this and it works fine with an Nvidia card using nouveau, this leads me to believe this to be a driver bug. I haven't tried in with the proprietary ati driver since I couldn't get it to work. Attached are Xorg and dmesg logs, the Xorg logs also have a Samsung screen in them since I wouldn't have been able to switch resolutions without it.
Created attachment 33617 [details] [review] Xorg log
Created attachment 33618 [details] [review] dmesg
Created attachment 33619 [details] Xorg log using nouveau
Since you are using kms, you should try a newer kernel (2.6.33 or drm-radeon-testing). If you want to try ums, boot with radeon.modeset=0 and try xf86-video-ati from git master.
I just tried it with a merge of 2.6.33 and drm-radeon-testing, the driver was already a git snapshot. This didn't behave any differently though. Then I tried it with UMS, which works fine. I'm attaching new logs for both cases. Hopefully this will narrow this down enough to get this fixed. If there is anything else I should test or provide, do ask.
Created attachment 33626 [details] dmesg 2.6.33+radeon-testing kms
Created attachment 33627 [details] Xorg.0.log 2.6.33+radeon-testing kms
Created attachment 33628 [details] dmesg 2.6.33+radeon-testing ums
Created attachment 33629 [details] Xorg.0.log 2.6.33+radeon-testing ums
(In reply to comment #0) > Using a Radeon HD 4650 with a LG W3000H screen, with either git drivers or the > ones that come with the ubuntu lucid beta, results in a black screen on boot. I'm getting something similar, and I have something for you to try: Start the system with UMS (i.e., the radeon.modeset=0 kernel parameter). When you are on the login screen, switch to a console, kill the desktop manager, and unload the "radeon" module. Once you unloaded it successfully, try manually loading it with the "modeset=1" parameter. If you get a high-res console then, start the desktop manager, and you should be fine. Fun thing is, that usually works for me, I get working KMS even on a dual-monitor setup on a Radeon HD4350 and an HD4870 that way, on the 4350 it will run stable for several weeks with an OpenGL accelerated KDE desktop without even showing graphical glitches. However, if I start without the modeset=0 parameter, my system will come up with a black screen once the module is (auto)loaded, and eventually freeze. I tried debugging via serial console, but nothing unusual came up. Running a 2.6.33 kernel from Debian experimental repository, as well as radeon X drivers from there (currently 6.13.0).
(In reply to comment #10) > Start the system with UMS (i.e., the radeon.modeset=0 kernel parameter). When > you are on the login screen, switch to a console, kill the desktop manager, and > unload the "radeon" module. Once you unloaded it successfully, try manually > loading it with the "modeset=1" parameter. If you get a high-res console then, > start the desktop manager, and you should be fine. I'll give that a try, if true this would mean that KMS is initializing something wrong and that the rest of the modesetting code isn't the problem here. Otherwise it should fail as well. I've tried a fresh radeon-testing checkout plus newest git drivers though, hoping that it might have 'accidentally' been fixed, but sadly it's still the same.
*** This bug has been marked as a duplicate of bug 27001 ***
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.