[oclug] Desktop size doesn't match monitor resolution

[Brad Barnett]

On Thu, 04 Oct 2007 19:11:54 -0400
"Aaron Wilcox" <aaron.wilcox at sympatico.ca> wrote:

> On Thu, 04 Oct 2007 12:17:42 -0400, Stephen Gregory
> <oclug at kernelpanic.ca>   wrote:
> 
> > On Thu, Oct 04, 2007 at 08:02:13AM -0400, Brad Barnett wrote:
> >>
> >> KDE may be displaying wrong values.
> >
> > the command:
> >
> > $ xdpyinfo |grep dim
> >
> > will display the dimensions that the X server is running at bypassing
> > KDE.
> >
> 
> aaron at osiris:~> xdpyinfo | grep dim
>    dimensions:    1680x1050 pixels (520x321 millimeters)
> aaron at osiris:~>
> 
> SaX2 indicates that my display resolution is set to 1920x1200, which is 
> 
> what the monitor thinks it's displaying.  I took a look at the X.org  
> configuration files, and there are two of them that seem to be updated  
> every time i fiddle around with stuff in SaX2.  One is  
> "/etc/X11/xorg.conf", the other is "/etc/X11/xorg.conf.saxsave".  The
> only   major differences between the two are in the "Modes" and "Screen"
>  
> sections.  "xorg.conf.saxsave" has had all the modelines and screen  
> settings with resolutions higher than 1680x1050 deleted.  I presume X11
> is   use "/etc/X11/xorg.conf.saxsave" to set the desktop resolution,
> would it   be OK to overwrite it with a copy of the other one?


Generally, when an app changes a config file of another app, it copies the
original as a backup (hence, 'saxsave').  X.org uses xorg.conf unless told
otherwise.

xorg.conf doesn't require any modelines in its config file for it to work.
 It can autodetect modes, monitor, everything these days.  If you want to
see what modes X started with, and perhaps changes made to the resolution
_after_ X started, look at the logfile in /var/log/.  

You seem to have some conflicting info, but usually monitors know what
they are displaying.  This is why I asked you, "What makes you think
something is wrong?".  Do you have reason to suspect that your monitor
is incorrect?  

For example, when you resize a window, such as an xterm, does window
dimension information pop up?  If so, what does it say when you make an
xterm the size of the entire screen?  Again, what visual clues are telling
you that the monitor is wrong about the dimensions it believes it is
displaying?

After all, if you are running something less stable (like Debian testing
or unstable, or even more unstable, Ubuntu), you may have a KDE build and
perhaps even conflicting libraries.  X.org is changing fast, and any
distro variant that changes fast is sure to have issues with this rapid
change.

So, again, look at your X.org log file, and generally trust your monitor
in most cases.  

If these things don't help, you're going to have to provide some real
detail.  For example, what distro are you using, what X version, and so
on...