I'm having trouble configuring X to run in 1280x768 (WXGA) resolution.
I'm running XFree86 4.2.0-72 from 20020123, the stock X that ships
with Redhat 8.0, which is the distro on this box. I have a 17"
widescreen LCD flatpanel from Planar (the XP17W), which runs in WXGA
as its native resolution. Initially, X was only showing the standard
4:3 resolution options--VGA, SVGA, and XVGA. I did some hacking on
XF86Config, adding the modeline

ModeLine "1280x768" 97.3 1280 1312 1680 1712 720 734 743 757

and changing the screen:display:modes line to

Modes "1280x768" "1024x768" "800x600" "640x480"

and eventually got it to use a new resolution, but with a weird twist:
X seems to be in 1280x768 (that's the dimensions of a screenshot), but
the panel comes up in 960x720! Not only do I have scroll the screen,
its horribly compressed, since its trying to fit a widescreen
resolution into a standard 4:3 frame. Does anyone have any idea what's
going on?
Aaron Davies