[Ilugc] LCD monitor configuration problem
- From: girishvenkatachalam@xxxxxxxxx (Girish Venkatachalam)
- Date: Mon Oct 9 14:22:39 2006
On Mon, Oct 09, 2006 at 01:32:43PM +0530, Arun Velusamy wrote:
Hi,
I am running Debian 3.1 sarge. I was using a 17' CRT monitor with
screen resolution 1024x768 & 61Hz, and Now, i have got a new IBM
ThinkVision LCD monitor. When i connected it, it says "Input signal out
of range". So i changed XF86Config-4 file to make 1280x1024 as default
screen setting.
Now i am get the GUI, but a black color box with "Input Signal out
of range" is moving all over screen. I think there is a problem with
refresh rates.
How can i configure the settings? Plz Help me guys.
Thanks in advance.
Regards,
Arun Velusamy.
Don't worry. We are all with you. Nobody actually gets X config right the first
time especially if you are using Debian. Unless the machine is old your chances
are slim of getting it right on new hardware.
Let me give a small theoretical dump.
I think LCD monitors work thro' CRT emulation. I must be wrong, but X at least
right now understand CRT picture tube funda better than LCD transistors I guess.
So you have a vertical refresh rate and a horizontal scan frequency. One is in
Hz and another in KiloHz. And for a given resolution and color depth, not all
values work.
So that is what you have to tune. Normally the PAL television screen shows 25
frames a second. And since it is interlaced scanning, the PAL refresh rate is
50 Hz. Two scans per frame.
Now, our computer monitors can do much much better. In fact I even hear 110 Hz.
If the refresh rate is too low, you perceive flicker. And if it is high enough,
it is soothing to the eyes.
And the other parameter is given in kiloHz and that is related to what your
monitor can actually do.
There is also a standard called DPMS using which the monitor can be queried for
its capabilities.
Anyway I think I have given you just too much useless information and no
practical advice.
All the best!
regards,
Girish
Other related posts: