recent (>=2009/2010) xorg servers can pretty much handle everything basic automatically. Rename /etc/X11/xorg.conf and see what you get automagically.

If it doesn't get it right, things can be difficult though, such as providing a refresh rate that the monitor doesn't like.

Here's some useful commands - run on opensolaris, incidentally.

• probe the current setup

• produces output to specification

hat tip - ubuntuforums

• produce an 'automagic' derived configuration for editing (courtesy of 'man Xorg)

root@brittain:~# xvidtune -show
"1024x768"     65.00   1024 1048 1184 1344    768  771  777  806 -hsync -vsync

root@brittain:~# gtf 1024 768 60

  # 1024x768 @ 60.00 Hz (GTF) hsync: 47.70 kHz; pclk: 64.11 MHz
  Modeline "1024x768_60.00"  64.11  1024 1080 1184 1344  768 769 772 795  -HSync +Vsync

root@brittain:~# svcadm gdm disable
root@brittain:~# Xorg -configure
[..]
root@brittain:~# mv /root/xorg.conf.new /etc/X11/xorg.conf