x server not reading xorg.conf?

[Jason Dravet]

>I don't know about the mouse side of things, but your 'preferred'
>resolution is actually set in Gnome using System > Preferences > Screen
>Resolution.
>
>The xorg.conf file tells the system what your screen is capable of, but
>the use of user defined screen resolutions allows each user to set what
>they would prefer as there resolution, instead of being stuff with
>whatever resolution the sysadmin for that machine thinks is 'Right
>(TM)'.
>
>It may well be that your mouse behavior is also user defined.

I discovered an older copy of my xorg.conf in /root.  X seems to be using 
that.  I did not realize X no longer defaults to using /etc/X11/xorg.conf 
first.  Getting rid of the old xorg.conf fixes my resolution and mouse 
problems.

Ok so then what is system-config-display supposed to do?  They both set the 
default resolution.  Also what happens when your resolution is not listed in 
screenresolution?

Thanks,