How to set modeline under xorg server 1.8.0

Robert Thompson xorg at
Fri Jun 11 04:56:33 PDT 2010

On 11/06/10 18:54, Another Sillyname wrote:
> On 11 June 2010 02:26, Another Sillyname<anothersname at>  wrote:
>> Hi
>> I have a setup which I've just upgraded to Fedora 13 with Xorg server
>> 1.8.0.  The setup has a Quadro FX 3400 card with an IBM T221 3840 x
>> 2400 monitor.
>> Under previous iterations of xorg i've output to the monitor as a
>> dualhead setup using 1920x2400 + 1920x2400 and it's worked pretty
>> well.
>> However under the new version of Fedora the xorg.conf file now gets
>> re-generated every reboot using udev to detect devices if I've
>> understood the docs properly.
>> Unfortunately the display is getting detected as a 3840x2400 screen
>> and is being output to at the wrong refresh rate, 50 hz rather then 25
>> hz, at least according to xrandr -q, and as a result the screen is
>> blank.  The xorg session is running however as I can vnc into it and
>> it's running fine.  I am using the nvidia driver from rpmfusion.
>> Given that xorg.conf is re-written every reboot how can I add both a
>> modeline and dualhead type config so that it 'sticks' after a reboot?
>> Thanks in advance.
> As a follow up to my earlier mail I've found that you can now put the
> xorg.conf in /etc/X11/xorg.conf.d and it will get read from there so
> that's solved that problem.
> My new problem is slightly different in that as the display is treated
> as two screens how do I get the screen background and panels to spread
> across as a single screen?
> i.e. at the moment my desktop background is shown as two identical
> images one on each screen, what I want is one background image spread
> across both screens.  Also any panels are limited to one screen rather
> then being spread across both screens.
> I know ATI had a concept called 'Big Desktop' for these situations but
> I could never get it working, does anyone have any ideas or
> workarounds to get it working now with an NVidia card?
> Thanks in advance.
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look for a "twinview" setting in your nvidia-settings panel, if having 
trouble finding the nvidia-settings via the GUI just open a terminal and 
type "gksudo nvidia-settings" and you are operating a better instance 
than you get from the menus in the (gtk) GUI anyway, at least after 
re-entering your password (provided you are member of wheel).

(in GUI should be "System->Administration->NVIDIA X Server Settings", in 
there  should be "X Server Display Configuration", look for button 
"Configure..." to right hand side - this gives you a situation where the 
picture you are saving by pressing enter after pressing 'printscrn' is 
the full width of both displays sum width.)

twinview is the closest I have seen to what you are asking for, is it 
available to you?

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