Red Hat Bugzilla – Bug 209024
X doesn't come up in proper resolution for LCD
Last modified: 2007-11-30 17:11:45 EST
I'm not getting X coming up in the proper resolution on my desktop box at home
with a Radeon X300SE. Attached via DVI to an LCD (1280x1024) and all I'm
getting with the stock X config is 800x600. Log file attached.
Created attachment 137614 [details]
x log file
Using the radeon option "DDCMode" "on" seems to cause it to DTRT...
You're using xorg-x11-drv-ati < 6.6.2-4, aren't you.
I'm 99% sure that I grabbed -4 to try last night -- I can double check when I
Yep, definitely have -4 and need the option in the config
I believe i'm seing the same problem in a slightly different incarnation.
I'm on 6.6.2-4 too, but running on an IBM ThinkPad T42 with a ATI Technologies
Inc RV350 [Mobility Radeon 9600 M10].
If doing a clean boot all the way to X, the resolution is fine. Any later
restarts of X, logout, runlevel changes etc. that would cause X to restart
triggers the problem for me and I also end in 800x600.
option "DDCMode" "on" does not work around this problem for me.
But i checked the Xorg.0.log file for interesting info and it looks like X for
some reason believes that I have an external monitor connected to the system
(which I don't - for the sake of clarity :o)). But since there really is no
monitor, practically all usable resolutions are "out of range" and we end in
To let X know that i really have no external monitor connected, I added:
option "MonitorLayout" "LVDS, NONE"
to xorg.conf and problem is now successfully worked around.
Created attachment 139194 [details]
T42 problematic X log file
Both Jeremy's and my own log file have :
(WW) RADEON(0): Failed to detect secondary monitor DDC, default HSync and
The problem is further that this faulty detection is used to find a common mode
for MergedFB - leaving us in 800x600.
Jeremy, have you seen this recently?