Red Hat Bugzilla – Bug 539785
X misidentifies monitor, prevents selection of many resolutions
Last modified: 2010-05-24 14:24:37 EDT
Created attachment 372668 [details]
log from the last boot to F11, monitor detected properly
Description of problem:
After upgrading from F11 to F12, the external monitor attached to my laptop dock is no longer detected properly, and no resolutions above 1280x1024 are available, despite that this monitor is capable of 1600x1200. This is quite annoying.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Boot with the laptop docked.
2. Log in to X.
Modes above 1280x1024 are rejected by the X server, and the monitor runs in 1280x1024.
1600x1200 should be selectable from "System > Preferences > Display" in GNOME,
and after selecting that the monitor should run in 1600x1200, as it used to in F11.
The monitor is a Sony Multiscan CPD-G520. The laptop is a Lenovo Thinkpad T61.
Created attachment 372669 [details]
log from F12, monitor not properly detected
Created attachment 372670 [details]
dmesg from F12
I've tried creating an xorg.conf containing the modeline used by X as indicated in the F11 xorg.0.log. This also fails. There seems to be no way to convince the new version of X to run my monitor at more than 1280x1024.
Looks like all required logs are aboard, setting keyword triaged and status to assigned.
This bug has been triaged
Fedora Bugzappers volunteer triage team
I've discovered that I can use xrandr to force X to run my monitor with the modeline I used in F11:
xrandr --newmode "1600x1200"x75.0 202.50 1600 1664 1856 2160 1200 1201 1204 1250 +hsync +vsync
xrandr --addmode VGA1 "1600x1200"x75.0
xrandr --output VGA1 --mode 1600x1200x75.0
This mitigates the problem for me a little, but it still should be looked into that the monitor isn't properly detected.
(In reply to comment #5)
> I've discovered that I can use xrandr to force X to run my monitor with the
> modeline I used in F11:
Of course, doing this causes the gnome-panel to vanish, despite that it still claims to be running, and it isn't sticky---I now have to do this every time I log in.
If there's anything I can contribute to getting this problem resolved, please don't hesitate to let me know.
If you can do it with xrandr you should be able to do it with xorg.conf. Read this page http://www.thinkwiki.org/wiki/Xorg_RandR_1.2 for a reasonable good guide.
This should be fixed by this kernel change upstream:
which is present in at least kernel-188.8.131.52-174.2.19.fc12 and later.
This is not fixed. I'm running 184.108.40.206-174.2.22.fc12.x86_64 right now, and my monitor is still misidentified.
I have a very similar problem on a Dell Latitude E6400 (Intel Corporation Mobile 4 Series Chipset, using the xorg-x11-drv-intel-2.9.1-1.fc12.x86_64 driver).
If I boot up undocked, then it's fine.
If docked, then it puts my panels on my laptop screen and a blank screen on the monitor. When I either open my laptop display or touch the GNOME "System > Preferences > Display", then I get 1024x768 on both laptop and monitor.
If I run this script, then I get the right size for my monitor with panels and all.
xrandr --output LVDS1 --mode 1440x900
xrandr --output VGA1 --mode 1920x1080
I'll give the guide above a try. The laptop worked fine until I upgraded to FC12 from FC11, however.
With kernel 220.127.116.11-70.fc12.x86_64, my monitor is now correctly identified.
This issue is now a "works-for-me", after upgrading to kernel-18.104.22.168-70.fc12.x86_64 and removing "nomodeset" from Grub. Just in case the rest of the Grub kernel line matters, it is:
kernel /boot/vmlinuz-22.214.171.124-70.fc12.x86_64 ro root=UUID=<removed> rhgb video=intelfb:mode=1440x900-32@70,mtrr=1 SYSFONT=latarcyrheb-sun16 LANG=en_US.UTF-8 KEYTABLE=us intel_tv_mode_set=off enable_mtrr_cleanup mtrr_chunk_size=128M mtrr_gran_size=128M
Marking closed per the last two comments.
I just upgraded to Fedora 13 (kernel 126.96.36.199-95.fc13.x86_64) and this exact problem is back. Whatever change was made in kernel-188.8.131.52-70.fc12.x86_64 to get rid of this problem did not make it to this kernel. The grub settings are the same.