[mythtv-users] Guides to calculating HorizSync and VertRefresh for xorg.conf?

[Denis Papathanasiou]

As a follow-up to this thread:
http://mythtv.org/pipermail/mythtv-users/2007-May/180183.html I'm
finding that it's nearly impossible to determine what the correct
values of HorizSync and VertRefresh should be.

This article in wikipedia
(http://en.wikipedia.org/wiki/Vertical_refresh#Cathode_ray_tubes)
suggests how to calculate the vertical given the horizontal, but
unfortunately, I know neither for my TV (it's a Sharp CRT, Model
27F631).

Are there any sites which have this data, e.g. tables listing
resolutions and corresponding HorizSync and VertRefresh values, or
more complete calculators or equation definitions?

Searching for xorg, ati (that's the card I'm using for TV out) and
HorizSync/VertRefresh brings back lots of results, but none are
consistent, even for the same, basic 800 x 600 resolution (one sites
says use x-y another says use a-b, etc.; they seem like ranges picked
at random).

The frustrating thing about this is that it's only the X server with
the problem; at boot, I can see the grub screen and initial boot
messages on the TV perfectly.

Any suggestions?