Red Hat Bugzilla – Bug 186111
fails to properly setup dual-head modes for radeon based displays
Last modified: 2007-11-30 17:11:27 EST
Description of problem:
system-config-display fails to setup a usable dual-head xorg.conf for either
individual displays or for spanning displays when the card is radeon driver based.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Attempt to setup dual-head display with any video card that uses the xorg
2. Choose either Individual Desktops or Spanning Desktops
3. Choose either a different card, or same card as on the Settings.. tab.
According to which of the 4 permutations you select above, you will either get:
The secondary monitor in power save mode but the mouse will travel off the side
of the primary monitor as if correctly using two monitors in one display.
The secondary monitor in power save mode but the mouse will not travel off the
side of the primary monitor, as if in plain single monitor mode.
The secondary monitor is a clone of the primary monitor, and the mouse will not
travel off the side of the primary monitor, as if in plain single monitor mode.
Both monitors on, and the mouse will move across them, and either as a double
wide :0.0 or as :0.0 and :0.1.
I think the problem is that Xinerama does not work with the radeon driver. The
radeon driver uses MergedFB mode. I will attach an xorg.conf that works as a
I will run any tests necessary to help with the resolution of this bug. Contact
me directly via email at email@example.com.
Created attachment 126415 [details]
This is the xorg.conf file I manually created that works.
Workaround is given in this thread:
Seems like the "ServerLayout" options are being ignored.
I think you need to add something like:
Option "CRT2Position" "RightOf"
to the "Device" section for your primary videocard.
That worked for me, at least...
Reporter, I am sorry, that we have left this bug unnoticed for so long, but
could you confirm please, that this bug still could be reproduced with the
latest updates of Fedora (FC6, F7, or Rawhide)?
And if it is reproducable, could we get also xorg.conf and Xorg.0.log generated
by system-config-display which didn't work? Of course, working
/var/log/Xorg.0.log would be useful as well.
No information requested provided, no joy for anybody -- closing this bug as
INSUFFICIENT_DATA. Reporter, if you could, please, reopen with additional