I have solved part of the problem. I determined upon a thorough examination of the xorg log and a lot of Googling that DDC and EDID were the problem. If I add the line
Option "DDC" "false" to the "Monitor" section of xorg.conf, it eliminates about half the extraneous monitor modes and now uses my first mode in xorg.conf for the login screen (although I still can't make it use my desired refresh rate). I still have too many resolution choices in Gnome, which are apparently due to EDID probing, but I cannot disable that. The two commands I've found for disabling EDID are "ignoreEDID" and "useEDID", but they apparently only work with the nvidia driver. I should also mention that I also saw "disableDDC" and "noDDC" as options for disabling DDC, so there may be some variation as to which option to use depending on the driver (I'm using the open source ati). I also had better success using a "generic" monitor and inputing the correct refresh rates manually rather than selecting my monitor using displayconfig-gtk, which may be due to some additional options that are written to xorg.conf when the "correct" monitor (Gateway VX900) is selected, and/or addition of the "virtual" screen option, but I didn't bother to pursue it. I gather from my research that the DDC and EDID "features" have been in X for a while, but were only fully activated in 7.3, although I could be mistaken. In any case, they are clearly not perfect, and X has no documentation I could find find about them. If others have success by disabling DDC and/or EDID, this should probably be bumped upstream to the X developers. -- Resolution on login screen incorrect https://bugs.launchpad.net/bugs/158387 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
