> Hi, I have managed to partially configure the settings for an LCD
> monitor that is rated at 1440x900 @60Hz (from the manual's specs - an
> AOC 193FW).  I did so by using SuSE's "Graphics Card & Monitor" tool in
> Yast.

Good.

> This got me as far as getting 1440x900, but the only refresh
> options available (KDesktop > Display) are 50 and 55Hz.  It doesn't look
> flash at 50, way better at 55Hz, and of course I want to be getting the
> rated 60Hz (hoping it looks even better).

That KDE refresh selector is kind of a pointless feature. Why would you
ever switch down? Configure the system for one frequency and do it
right. It's made for CRT monitors anyway.

With LCD monitors, there are 2 things to know:

1) The resolution (correct: number of pixels) has to always be exactly
the same as the number of pixels of the LCD panel, otherwise there is
serious loss of quality to the point of the whole monitor being useless.
So no choice here, the monitor comes with a number and that's it.

2) Because the delay of switching pixels of an LCD panel is so
astronomically high, there never will be any flicker caused by a
vertical refresh which is too low. Therefore this is basically a
pointless number; the monitor will probably be using internally what it
wants to anyway and there's nothing you can do about that.
However, the rate at which the data goes from the computer into the
monitor's frame buffer needs to be within the limit of the monitor's
input circuitry. As this has nothing to do with reducing flicker (as
with CRTs), you can put what you want, within the limit of course.
That's why 60Hz almost always gets you there. Of course someone could
make a really cheap fixed frequency input circuitry, in which case only
60Hz will get you there (monitor will give sync error otherwise).

Again: the refresh rate from computer to LCD monitor only has to match
the input circuitry of the monitor and has no effect on flicker of the
display.

That was the background, now to the problem.

When I look in the monitor model list under AOC, there are only what
looks like CRTs. Go for model "LCD", and pick a generic resolution and
60Hz. That's all you should need to do, however, there's 1440x900 only
with 70Hz. Ok 2 options: try that first (make sure you use the test
function in SaX2, if you're left with an Xorg config with which the
monitor doesn't sync you're somewhat screwed). Next, still select
[EMAIL PROTECTED], and go into the Sync frequencies tab and reduce the upper
limit of vertical from 72 to 62. If that works, file a bug at
bugzilla.novell.com for openSUSE saying that [EMAIL PROTECTED] is needed in
the "--> LCD" list.

Oh and you can ignore the "wrong sync frequencies will damage your
monitor" with LCDs. Though don't try and crank it, you're wasting your
time, the picture can't get any better.

To find out the sync frequencies reliably, have the monitor tell you. If
it doesn't, you're into a bit of fudging. All these commands are
probably right:

  xwininfo -root  (thanks Nick)

  xvidtune

  nvidia-settings  (if you have an nvidia card and use the nvidia driver)

It would be interesting to see if any of those give wrong values (the
monitor should always be right). If there is any doubt left, the
oscilloscope is definitely right.

There should be no need to edit the Xorg config file with a text editor,
SaX2 ought to do it (and does for me). Of course if you prefer
$TEXTEDITOR go for it.

Volker

-- 
Volker Kuhlmann                 is list0570 with the domain in header
http://volker.dnsalias.net/     Please do not CC list postings to me.

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