From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.3)
Gecko/20050104 Red Hat/1.4.3-3.0.7
Description of problem:
I have a laptop Dell D600 which has a 1400x1050 LCD display. Now this
display _needs_ to have the reslution set to 1400x1050, if I try to
alter it with CTRL-ALT-+ or xrandr the displat goes black. Now this
isn't a major problem until I connect the laptop to a projector. Since
the projector can't handle resolutions higher then 1280x1024
(otherwise it goes black and complains about beeing out of sync) I end
up with having to use _either_ the built in LCD panel or the projector.
To remedy this I tried to set up different resolutions on the external
and internal port, but with little success. My Xfree86Conf is attached.
The graphics adapter in the laptop is a
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon R250 Lf
[FireGL 9000] (rev 02)
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Attach a projector that can't handle 1400x1050 resolution.
2. Note how you can't see the image on both the projector and LCD
Created attachment 110493 [details]
I've reviewed this bug report and done some preliminary investigation
which seems to indicate that this problem appears to be a
configuration issue rather than a bug in the X server or video
In order to configure the server to do what you want, you will need
to edit the X server config file by hand and change some options,
which are describe on the "radeon" driver manpage. You may need
to experiment with different options until you find a setup that
meets your specific requirements.
If you require assistance configuring the server, please contact
Red Hat Global Support Services directly at 1-888-RED-HAT1 for
technical support, and mention this bug report to the
Setting status to "NOTABUG" as per above assessment.
In deed it was an configuration issue.
Adding the line
Option "CloneMode" "1280x1024"
to the "device" section of /etc/X11/XF86Config solved the problem