You should be able to run "xvidtune" in order to get the right modeline. Set your screen as you like then click on "show." This will kick out a modeline. Find the modline in your /etc/X11/XF86Config file, in the appropriate section, that starts with the same desktop size as xvidtune reports.For example something along the lines of "1024x768." Comment that line out and paste the new modeline xvidtune created into the file.Save the file and restart X.
Well it's remembering the resolution setting. The problem is that it's not remembering the geometry settings like the pincusion, trapezoid, etc. so the screen is all bent out of shape (in the proper resolution).
- Bart