IV. Fine Tuning and Extra Tips
 

A. Higher Resolutions and Vertical Refresh Rates
 
1. A number of monitors exist that are not in the Xconfigurator list. These can be found in /usr/X11R6/lib/X11/doc/Monitors file. To get the best resolution out of your video card and monitor you may have to do some massaging of the X window configuration file, /etc/X11/XF86Config. Here's an example:
 
a. Terry Jones has a 19" Hitachi, model CM751U, monitor. It can operate at a horizontal sync rate of 31-95kHz and a vertical sync rate of 50-160 Hz. The physical screen resolution is 1600x1280. Running 'X -probeonly' and piping the results to a file reveals that the dot clock on his video card can run at 280MHz, and the amount of video memory he has is 4Mb.

b. While doing a normal configuration of X with Xconfigurator, the highest resolution it offers is 1280x1024.

c. Looking in the /usr/X11R6/lib/X11/doc/Monitors file there are several entries for 1600x1200. Choose one that has a Vertical Refresh rate between 70-80 Hz. (Avoid 60 Hz as this is the rate that flourescent lights flash at and staring at a screen that has the same frequency can cause headaches and irratability.) There is one entry that refreshes at 75Hz. Take the line that starts with the word "Modeline" and insert it near the bottom of the section labelled "Monitor section" but before the EndSection line.

d. In the next section, the "Screen sections," find the section that corresponds to the server installed on the machine. This will either be in the SVGA or Accelerated Section. In the Modes line add the mode you just added to the "Monitor section." This is what it should look like:
 

Modes "1600x1200" "1280x1024" "1024x768"
e. Save the file, exit the X window session (if started) and restart with startx. Everything *should* work correctly.

f. Fine tuning may need to be done either with xvidtune or on-monitor controls to center and size the image. Using xvidtune you can adjust the timings and push the "show" button to dump a standard XF86Config style Modeline line. This can then be copied into the XF86Config file in place of the original line you placed.