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Old 02-01-2010, 09:53 PM   #1
ratcateme
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Distribution: CentOS 5.4
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CentOS 5.4 screen resolution

i have been searching for the past few days on how to do this i have found many articles all telling me slightly different ways of doing so but none have worked.
the monitor i am using displays at 1680x1050@60Hz
however most access will be from a laptop running at 1366x768 through VNC
i have the VNC working thats not a problem my current problem is that when i turn it on the screen defaults to 1600x1200@60Hz
when i go to System>Preferences>Screen Resolution the options i get are
1600x1200, 1280x1200,1024x768, 800x600, 640x480
however when i change to something other than 1600x1200 the refresh rate changes to 85Hz and cannot be displayed by my monitor so i have to wait for it to default back, not that i want to change it to any of those in the long term

/etc/X11/xorg.conf looks like this (i have only edited the Modes line)
Code:
# Xorg configuration created by system-config-display

Section "ServerLayout"
        Identifier     "single head configuration"
        Screen      0  "Screen0" 0 0
        InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "InputDevice"
        Identifier  "Keyboard0"
        Driver      "kbd"
        Option      "XkbModel" "pc105"
        Option      "XkbLayout" "us"
EndSection

Section "Monitor"

 ### Comment all HorizSync and VertSync values to use DDC:
        Identifier   "Monitor0"
        ModelName    "Philips 200W (autoconfigured)"
 ### Comment all HorizSync and VertSync values to use DDC:
        HorizSync    30.0 - 93.0
        VertRefresh  56.0 - 85.0
        Option      "dpms"
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "i810"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "Videocard0"
        Monitor    "Monitor0"
        DefaultDepth     24
        SubSection "Display"
                Viewport   0 0
                Depth     24
                Modes    "1366x768" 
        EndSubSection
EndSection
Thanks Scott.
 
Old 02-02-2010, 09:37 AM   #2
amon
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More info on the configuration file and each of the options can be found in xorg documentation: http://www.freebsd.org/doc/handbook/x-config.html

The value I think you are interested in here is the VertRefresh.

More information about that value can be found in the man page here:
http://www.x.org/archive/X11R6.8.0/doc/xorg.conf.5.html

It is specified here as a range. The value on the right hand side of this (in your configuration) is "85" which your screen keeps "reverting" to. I would suggest changing this to whatever the value is that your monitor requires. So:
Code:
Section "Monitor"

 ### Comment all HorizSync and VertSync values to use DDC:
        Identifier   "Monitor0"
        ModelName    "Philips 200W (autoconfigured)"
 ### Comment all HorizSync and VertSync values to use DDC:
        HorizSync    30.0 - 93.0
        VertRefresh  56.0 - 60.0
        Option      "dpms"
EndSection
Best thing to do is make a backup copy of your xorg.conf file and try running the xorg configuration tool. Most distributions have a choice configuration tool for this.

You can try setting this value by hand also.
 
Old 02-03-2010, 05:20 AM   #3
ratcateme
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thanks for the help
i tried that and looked through the manual pages but still nothing changed.
its almost as if its not reading the xorg config file
is that possible? i have been looking through the logs but they are so long its hard to know what im looking at if its good or bad
i did find this
Code:
(II) I810(0): Monitor0: Using hsync range of 30.00-93.00 kHz
(II) I810(0): Monitor0: Using vrefresh range of 56.00-85.00 Hz
(II) I810(0): Monitor0: Using maximum pixel clock of 170.00 MHz
(II) I810(0): Not using mode "1366x768" (no mode of this name)
(II) I810(0): 11480 kBytes additional video memory is required to
	enable tiling mode for DRI.
(--) I810(0): Virtual size is 1600x1200 (pitch 1600)
(**) I810(0):  Built-in mode "1600x1200"
(**) I810(0):  Built-in mode "1280x1024"
(**) I810(0):  Built-in mode "1024x768"
(**) I810(0):  Built-in mode "800x600"
(**) I810(0):  Built-in mode "640x480"
(II) I810(0): Attempting to use 60.00Hz refresh for mode "1600x1200" (85a)
(II) I810(0): Attempting to use 85.02Hz refresh for mode "1280x1024" (858)
(II) I810(0): Attempting to use 85.00Hz refresh for mode "1024x768" (854)
(II) I810(0): Attempting to use 85.14Hz refresh for mode "800x600" (852)
(II) I810(0): Attempting to use 85.01Hz refresh for mode "640x480" (850)
i can now see where it gets the modes from does this mean that i am not going to be able to set it 1366x768?

Thanks
Scott.
 
Old 02-03-2010, 05:35 AM   #4
amon
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Quote:
Originally Posted by ratcateme View Post
its almost as if its not reading the xorg config file
is that possible?
Yes it is possible but unlikely.

Looking at your log it appears to say it doesn't want to use "1366x768" which you have set in your config file. And it then goes on to say about using one of the other resolutions.

I'm assuming that CentOS may have another layer of configuration for the screen. Is there a GUI configuration tool that you have available to you as part of your desktop environment (KDE/Gnome) or whichever you use? Perhaps it may be best to use this or look into that tool.

Which version of CentOS are you using?
This may help: http://www.linuxtopia.org/online_boo...iguration.html

Can you copy here your xorg.conf file as it is now?
 
Old 02-03-2010, 05:53 AM   #5
ratcateme
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i atempted to use system-config-display
it changed my xorg.conf but on after pressing Restarting the window system it went back to 1600x1200
it offered the option of 1680x1050 i picked that to be safe for now.
i check the log after and the same section i posted before look like:
Code:
(II) I810(0): Monitor0: Using hsync range of 30.00-93.00 kHz
(II) I810(0): Monitor0: Using vrefresh range of 56.00-85.00 Hz
(II) I810(0): Monitor0: Using maximum pixel clock of 170.00 MHz
(II) I810(0): Not using mode "1680x1050" (no mode of this name)
(II) I810(0): Not using mode "1600x1024" (no mode of this name)
(II) I810(0): Not using mode "1440x900" (no mode of this name)
(II) I810(0): Not using mode "1400x1050" (no mode of this name)
(II) I810(0): Not using mode "1280x960" (no mode of this name)
(II) I810(0): Not using mode "1280x800" (no mode of this name)
(II) I810(0): Not using mode "1152x864" (no mode of this name)
(II) I810(0): 11480 kBytes additional video memory is required to
	enable tiling mode for DRI.
(--) I810(0): Virtual size is 1600x1200 (pitch 1600)
(**) I810(0): *Built-in mode "1600x1200"
(**) I810(0): *Built-in mode "1280x1024"
(**) I810(0): *Built-in mode "1024x768"
(**) I810(0): *Built-in mode "800x600"
(**) I810(0): *Built-in mode "640x480"
(II) I810(0): Attempting to use 60.00Hz refresh for mode "1600x1200" (85a)
(II) I810(0): Attempting to use 85.02Hz refresh for mode "1280x1024" (858)
(II) I810(0): Attempting to use 85.00Hz refresh for mode "1024x768" (854)
(II) I810(0): Attempting to use 85.14Hz refresh for mode "800x600" (852)
(II) I810(0): Attempting to use 85.01Hz refresh for mode "640x480" (850)
xorg.conf (changed by system-config-display)
Code:
# Xorg configuration created by system-config-display

Section "ServerLayout"
	Identifier     "single head configuration"
	Screen      0  "Screen0" 0 0
	InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "InputDevice"
	Identifier  "Keyboard0"
	Driver      "kbd"
	Option	    "XkbModel" "pc105"
	Option	    "XkbLayout" "us"
EndSection

Section "Monitor"

 ### Comment all HorizSync and VertSync values to use DDC:
 ### Comment all HorizSync and VertSync values to use DDC:
	#VertRefresh  56.0 - 85.0
	Identifier   "Monitor0"
	ModelName    "Philips 200W (autoconfigured)"
 ### Comment all HorizSync and VertSync values to use DDC:
	HorizSync    30.0 - 93.0
	VertRefresh  56.0 - 60.0
	Option	    "dpms"
EndSection

Section "Device"
	Identifier  "Videocard0"
	Driver      "i810"
EndSection

Section "Screen"
	Identifier "Screen0"
	Device     "Videocard0"
	Monitor    "Monitor0"
	DefaultDepth     24
	SubSection "Display"
		Viewport   0 0
		Depth     24
		Modes    "1680x1050" "1600x1200" "1600x1024" "1440x900" "1400x1050" "1280x1024" "1280x960" "1280x800" "1152x864" "1024x768" "800x600" "640x480"
	EndSubSection
EndSection
 
Old 02-03-2010, 06:58 AM   #6
amon
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You are not alone. http://johnsu01.livejournal.com/73699.html

The errors:
Code:
(II) I810(0): Not using mode "1680x1050" (no mode of this name)
(II) I810(0): Not using mode "1600x1024" (no mode of this name)
(II) I810(0): Not using mode "1440x900" (no mode of this name)
(II) I810(0): Not using mode "1400x1050" (no mode of this name)
(II) I810(0): Not using mode "1280x960" (no mode of this name)
(II) I810(0): Not using mode "1280x800" (no mode of this name)
(II) I810(0): Not using mode "1152x864" (no mode of this name)
Code:
(II) I810(0): Not using mode "1366x768" (no mode of this name)
Are saying that either your monitor or video hardware are not happy using that resolution. Check with your video card and monitor documentation for supported modes.

This is stolen from someone else:
Quote:
A short history of standard resolutions:
Hercules mono: 720x348
CGA: 320x200, 640x200
EGA: 640x350
VGA: 640x480
SVGA: 800x600
XGA: 1024x768
SXGA: 1280x1024
Are you using a standard 4:3 ratio screen? Perhaps it is worth trying a standard ratio in your xorg.conf

The xorg.conf resolutions are picked from left to right so it will try "1680x1050" when this fails it will move onto "1600x1200" and so on. So perhaps you should set "1280x1024" Or whatever resolution you know your system to be happy with to be the first one in that list and then reboot. If that works try putting another one (that you desire) in front of it in the list. This may be a case of some trial and error.

If you are still having problems can you detail the make/model of both your video card and monitor.

Would I be correct in saying that you have solved the original refresh rate problem? And we are now just dealing with the resolution?
Last edited by amon; 02-03-2010 at 07:00 AM. Reason: syntax error
 
Old 02-03-2010, 08:57 PM   #7
ratcateme
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Distribution: CentOS 5.4
Posts: 59

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ok so i looked through that link tried all the Modelines and got nowhere.
the graphics card is Intel 82865G built on the motherboard
i read a few links that took me down the path of removing the monitor and then just using VNC
so far i have managed to get it working at 1024x768 on VNC but i cannot get 1366x768 (resolution of the laptop VNC clients)
now my xorg.conf looks like this:
Code:
# Xorg configuration created by system-config-display

Section "ServerLayout"
	Identifier     "single head configuration"
	Screen      0  "Screen0" 0 0
	InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "InputDevice"
	Identifier  "Keyboard0"
	Driver      "kbd"
	Option	    "XkbModel" "pc105"
	Option	    "XkbLayout" "us"
EndSection

Section "Monitor"

	Identifier   "Monitor0"
 ### Comment all HorizSync and VertSync values to use DDC:
	HorizSync    30.0 - 93.0
	VertRefresh  56.0 - 60.0
EndSection

Section "Device"
	Identifier  "Videocard0"
	Driver      "vesa"
	Option	    "NoDDC"
EndSection

Section "Screen"
	Identifier "Screen0"
	Device     "Videocard0"
	Monitor    "Monitor0"
	DefaultDepth     24
	SubSection "Display"
		Viewport   0 0
		Depth     24
		Modes    "1024x768" "800x600" "640x480"
	EndSubSection
EndSection
i generated that with system-config-display
and on reboot if i VNC in i get a screen that is 1024x768
is there another graphics driver i could use that might work better and allow 1366x768 or something?
thanks scott.
 
Old 02-04-2010, 11:00 AM   #8
amon
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Right, just to confirm:
  1. The machine itself has a graphics card and a screen set up that can do 1680x1050@60Hz.
  2. The server is happy to operate at this configuration. And now we have sorted the vert refresh the screen stays on after reboot.
  3. You want to access this machine from laptop(s) with a resolution of 1366x768.
  4. You want the computer to run its display at 1366x768@60hz so it fits on the laptop screens properly.

For drivers you need to let us know what video hardware you have (make/model).
 
Old 02-04-2010, 08:36 PM   #9
ratcateme
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Distribution: CentOS 5.4
Posts: 59

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thanks for all the help.
I have been looking around more i finally got it to display at 1024x768 which sort of works on the main moniter and on the VNC laptop
so now i think i will leave it like that if i read more later i might try again but for now it should be fine


thanks
scott.
 
  


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