Modifying xorg.conf to set up monitor to 1280x1024 60hz refresh rate.

glore2002 · 09-11-2008, 02:08 PM

Hi Back,

Now if I right click on my desktop and choose Configure Desktop->Display, I see my monitor is displaying 1280x1024 at 50hz refresh rate. If I try to change the refresh rate, available options are: 50 or 54.

My monitor (Samsung 732nplus) has a recommended refresh rate of 60hz and a recommeded resolution of 1280x1024. So, resolution is ok but refresh rate should be changed to 60.

What parameter/s should I change to set refresh rate to 60?

I've tried to change this to nVidia X server settings but then I wasn't able to boot my system again into X (as I've mentioned in a previous post).

This is my xorg.conf file (screen related sections):

Code:

Section "Monitor"
    Identifier  "My Monitor"
    HorizSync   31 - 81
    VertRefresh 56-75
EndSection

Section "Device"
    Identifier  "VESA Framebuffer"
    Driver      "nvidia"
EndSection

Section "Screen"
    Identifier  "Screen 1"
    Device      "VESA Framebuffer"
    Monitor     "My Monitor"
    DefaultDepth 24
    Subsection "Display"
        Depth       8
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       24
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       32
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
EndSection

Thanks,
Glore2002.-

pixellany · 09-11-2008, 02:20 PM

I don't pretend to totally understand how this works. Things I have used successfully:

1. Set the monitor vert. refresh to 59.9-60.1

2. Use a modeline (generate using gtf)

keefaz · 09-11-2008, 02:24 PM

Could you set it with the nvidia-settings program ?

pixellany · 09-11-2008, 02:28 PM

I am running a 1920x1200 LCD on an Nvidia card (nvidia driver). The vert refresh was set to 50-70, and xrandr said it was actually running at 50. Curiously, it gives other modes available as follows:

Code:

1920x1200      50.0* 
   1680x1050      51.0     52.0  
   1600x1200      53.0  
   1600x1024      54.0  
   1440x900       55.0  
   1400x1050      56.0     57.0     58.0  
   1280x1024      59.0     60.0  
   1280x960       61.0 
<snipped>

Out of curiousity, I changed the vert refresh to 58-62, and nothing changed. I assume this means it is working off of the data it gets directly from the monitor.

The screen does not flicker and looks great, so I don't care to find out what's going on---at least for now....

glore2002 · 09-11-2008, 02:31 PM

Quote:

Originally Posted by keefaz

Could you set it with the nvidia-settings program ?

The nVidia setup program gave me the possibility to change refresh to 60 but it generates a new xorg.conf. With this new xorg.conf my computer couldn't boot up.

Glore2002.-

keefaz · 09-11-2008, 02:39 PM

Just use show preview after you click "Save to X file...", click cancel after that
Then note the options in "Screen" section, and add Screen option in xorg.conf
In the hope that is not the option that makes X un-startable though

pixellany · 09-11-2008, 02:39 PM

I used nvidia-settings and changed the refresh rate from "auto" to 60. xrandr then said that i now had 2 options for the 1920x1200 mode: 50 and 100. The refresh rate for the other modes was the same as before.

I have NO CLUE what is going on.....

keefaz · 09-11-2008, 02:44 PM

Be carefull, I just noticed the xorg.conf generated by nvidia-settings does not use the same Identifier names as the original xorg.conf in sections!!!

No wonder X will not start if you just copy one section for example, the identifier names must match between sections

Woodsman · 09-11-2008, 02:55 PM

Quote:

What parameter/s should I change to set refresh rate to 60?

This sounds much like the problem I experienced and shared:

https://www.linuxquestions.org/quest...701/page2.html

I use a Samsung 712N monitor with the same basic display specs. I use the proprietary nvidia drivers. The solution I discovered solved the incorrect reporting of the display settings.

I hope this helps.

keefaz · 09-11-2008, 03:23 PM

Thanks Woodsman for the tip about DynamicTwinView, much appreciated

glore2002 · 09-11-2008, 05:40 PM

#1: Woodsman: Your research work deserves an "A" :-)
#2: Now I can choose between 60 and 75hz. It works OK.
#3: What I finally added was:

Code:

Option "DynamicTwinView" "false"

to the Screen section of my xorg.conf. That solved the problem.

Thanks to all of you. You're the best source of information I ever had!!!

Glore2002.-