Please apply this patch: http://www.botchco.com/alex/xorg/superpatch/superpatch_radeon.diff inorder to fix output handling issues with the current modular xorg radeon driver (i.e.the driver does not detect monitor modes correctly, which is a serious limitation). For more information about what problems this patch solves see bug #3621 at freedesktop.org (https://bugs.freedesktop.org/show_bug.cgi?id=3621). Note that this patch is not scheduled for inclusion in final xorg 7.0 which leaves any dual head radeon users in pain since the radeon driver fails to detect correct monitor modes (I for one cannot use any resolution higher than 1024x768 on a external monitor with vanilla xorg 7.0rc2 - the same monitor was able to run 1280x1024 with xorg 6.8.2). Reproducible: Always Steps to Reproduce: 1. in stall modular xorg 2. setup merged fb/xinerama with two screens. 3. start x Actual Results: The second monitor is only able to run in a few selected modes or will not run at all. Expected Results: Use the configured(and supported) resultions on both monitors.
Marking this upstream, pending commit to X.Org CVS. The patch's author has said there's no way it will be ready for 7.0, meaning the patch just doesn't work right yet. Therefore we definitely shouldn't be adding it ourselves, over the wishes of its author.
You have a point it may still be unstalble, although it does solve my problem and seams stable enough at my end. Making a overlay and compiling the ati drivers from that one until it goes into mainstream code is properly the best way to go.
Sounds like a great idea. Feel free to post a version of the patch here that applies cleanly to modular, in case anyone else happens across it.