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thllgo 10-07-2003 08:27 PM

LCD Monitor problem

I just got a new LCD monitor, Planar 191M from Dell. The monitor works great with XP and nearly great with Mandrake 8.0. There is a strip at the top about 30-40 pixels wide that is shifted right about 7-10 pixels.

I am set at 1024x768x16. I used custom setting at Horz. 31.5-67 and Vert 50-71.

Using the plug and play setting or various other generic settings don't improve anything.

The rest of the screen is fine.


faheyd 10-09-2003 03:16 AM

I'm not saying it will fix anything, but your custom settings are not correct according to the user manual at .
And even that manual had conflicting info as to the settings. According to the preset configs and the spec page, you should be able to set:
vert to 50.00 - 75.06 (hz)
horz to 31.47 - 79.80 (khz)

Please read the manual again and see if you agree. You can then try it. As always with X settings, out of range settings can blow the monitor. If you really really want to be safe, send an email with your requested settings and see if you get a response from the people at dell or planar.

Another program you can try is 'xvidtune', but I've always had problems getting the settings to 'stick' with that program.

You can also look at the /var/log/XFree86.0.log file and see if there is anything strange in there.

Please post your results so that you may help others.

thllgo 10-09-2003 08:30 AM

I found the problem. Apparently if you have an ATI, which I do, you have to put an option in for the card, not just the monitor. The following fixes the problem, in the section

Section "Device"
Option "composite_sync" "False" # this line fixes all

Putting that option in fixes a sync problem. I did this and WHAM, great screen. It seems that the ATI cards don't sync well with composite sync to an LCD screen, :rolleyes: any LCD screen. I read where someone else had the problem with an ATI Mach 64, I have the Radeon, but both use the ATI driver.

It be happy :D

thllgo 10-09-2003 08:39 AM


Originally posted by faheyd should be able to set:
vert to 50.00 - 75.06 (hz)
horz to 31.47 - 79.80 (khz)...

I read the manual and set the values to a sub set that is used by 1024x768 XGA and VESA standards. The higher values you show are used by higher resolutions according to the manual. I was also going by the values XP uses and XP was working quite well at much lower values.

faheyd 10-09-2003 02:29 PM

Whatever floats your boat. I do know that the higher the scanning freq's, the 'less' tired your eyes get due to screen flicker (which is invisible most of the time).

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