Folks, a friend helped me dig into the X server sources, and I now understand this situation much better.
Many have suggested a work-around that involves setting explicit HorizSync and VertRefresh values. This will not help if your monitor is connected to the DVI port of the ATI Radeon X1300 series, (and probably related cards) because the DVI configuration carefully ignores any xorg.conf input, and goes with what is returned by the EDID BIOS transfer. The root cause here is flaky EDID BIOS transfer. My friend and I have posted up-to-date work on fault isolation on that EDID BIOS tranfer in Red Hat Bugzilla bug 236416 at: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=236416 By adding in a sleep(2) just before the EDID BIOS read, we get a partial or complete fetch of the monitor data. Apparently the latest 7.2 X server in use by Ubuntu 7.04 is able to time things differently by fiddling with the module load order. (I have Xorg.0.log file output showing failed or successful EDID transfers depending on the addition or deletion of a module load i2c line.) I've searched the x.org bug tree and found a relevant bug: https://bugs.freedesktop.org/show_bug.cgi?id=10238 But the understanding is not as detailed as what my friend and I have recorded n the Red Hat Bugzilla bug. I think that even the Fedora folks working this bug think the remedy is code to set explicit HorizSync and VertRefresh values, because that seems to be what is in the patch for Fedora 7 test3 which some people report as helpful. -- [regression] 7.2 broke vesa: "No matching modes found" https://bugs.launchpad.net/bugs/89853 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
