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mduduzi
12-17-2007, 03:21 PM
Hi guys, i would like your help in this matter.

I am running knoppix dvd v5.1 on hdd installation, but im experiencing problems with my monitor. The refresh rate is set to 76Hz by default on start-up but this is too high for my 19in samsung monitor. Flow lines are visible moving from the bottom to the top of the screen. I have tried to follow what the source of the problem is and i finaly came to realise that xorg might be responsible in the X11 system. So i opened the xorg configuration file in /etc/X11 by running the xorg.conf file.

After opening this config file, the information i found concerining the monitor which i want to run at 1280x1024 resolution is show below

Section "Monitor"
Identifier "Monitor0"
Option "DPMS" "true"
VendorName "SAM"
ModelName "SAM02ad"
HorizSync 30 - 81 # DDC-probed
VertRefresh 56 - 75 # DDC-probed
# These are the DDC-probed settings reported by your monitor.
# 1280x1024, 75.0Hz; hfreq=79.98, vfreq=75.03
ModeLine "1280x1024" 135.00 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync
# Extended modelines with GTF timings
# 1280x1024 @ 100.00 Hz (GTF) hsync: 108.50 kHz; pclk: 190.96 MHz
ModeLine "1280x1024" 190.96 1280 1376 1520 1760 1024 1025 1028 1085 -HSync +Vsync

What i would like to know is how can i edit this conf file to adjust my refresh rate (frequency) of the monitor? Or if I'm completely mistaken about the source of the problem, please point me in the correct direction since im starting to find my way as a beginner in the world of editing such deep system information.

Thanx

hal8000
12-17-2007, 08:01 PM
Use apt-get install xmodelines

usage is:
xmodelines -x 1280 -y 1024 -r 70

to generate a modeline or online:

http://xtiming.sourceforge.net/cgi-bin/xtiming.pl

Use the timing line in your xorg.conf file.

Make a backup of your old xorg.conf and comment out unwanted entries

mduduzi
12-20-2007, 07:19 AM
The problem is that i dont have internet access at the moment because of connection problems to my provider. Is the anyway of solving the problem without using apt-get? Can i download the xtiming software and apply it without internet?

What is the timing line in the xorg.conf file? Please point or highlight it on the xorg.conf file portion i have pasted before.

hal8000
12-22-2007, 04:48 PM
Ok, the modeline below is caluclated from the online link in my previous post. If you copy and paste it into your
/etc/X11/xorg.conf and comment out other lines with a # this should work.

Make sure that your graphics card and monitor can run at 75KHz, the refresh rate is 70Hz


Modeline "1280x1024@70" 141.82 1280 1312 1848 1880 1024 1044 1056 1076

Horizontal sync frequency: 75.43 kHz