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xrandr maximum resolution is well below the preferred

My monitor has a preferred resolution of 1440x900 (A number located by booting to Puppy which displays correctly). I have use Ubuntu, Debian, and Mint with this computer and they have all been fine with the resolution. But withg CentOS 32b on a Dell Latitude D620 when I go to xrandr it outputs this:

Code:

[~]$ xrandr

xrandr: Failed to get size of gamma for output default

Screen 0: minimum 800 x 600, current 1024 x 768, maximum 1024 x 768

default connected 1024x768+0+0 0mm x 0mm

  1024x768      61.0* 

  800x600        61.0

I did some reaserch and I found that I should add a new mode so I did what they said and got this:

Code:

[~]$ cvt 1440 900

# 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz

Modeline "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

[~]$ xrandr --newmode "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

xrandr: Failed to get size of gamma for output default

I then tried to find out how to fix this "gamma" issue and found several solutions, none of which worked. Does anyone have any idea how I could get this working?

Also, from what I can tell it's using Intel integrated graphics.

FWIW, I create an xorg.conf file to allow me to access the full resolution on my Soyo monitor. I use gtf to get the proper modeline:

Code:

$ gtf 1680 1050 60



  # 1680x1050 @ 60.00 Hz (GTF) hsync: 65.22 kHz; pclk: 147.14 MHz

  Modeline "1680x1050_60.00"  147.14  1680 1784 1968 2256  1050 1051 1054 1087  -HSync +Vsync

then paste the modeline into the Monitor section of my xorg.conf file:

Code:

Section "Monitor"



    #UseModes    "Modes0" #monitor0usemodes

    Identifier    "Monitor0"

    VendorName    "Monitor Vendor"

    ModelName      "Monitor Model"

    DisplaySize    432    270

    HorizSync      30.0 - 86.0

    VertRefresh    56.0 - 76.0

    ModeLine      "1680x1050" 147.1 1680 1784 1968 2256 1050 1051 1054 1087 -hsync +vsync

    #Option        "PreferredMode" "1680x1050"

EndSection

and add the mode to the Screen section (along with a couple of vesa modes that should always work):

Code:

Section "Screen"

    Identifier    "Screen0"

    Device        "Card0"

    Monitor        "Monitor0"

    Option        "IgnoreEDID" "TRUE"

    SubSection    "Display"

        Modes    "1680x1050" "1440x900" "1280x1024"

        Viewport    0 0

        #Modes      "1680x1050" "1600x1200" "1280x1024"

        Option        "IgnoreEDID" "TRUE"

    EndSubSection

EndSection

Okay, I did what you suggested. I used gtf and got this:

Code:

[~]$ gtf 1440 900 60



  # 1440x900 @ 60.00 Hz (GTF) hsync: 55.92 kHz; pclk: 106.47 MHz

  Modeline "1440x900_60.00"  106.47  1440 1520 1672 1904  900 901 904 932  -HSync +Vsync

Then I created an /etc/X11/xorg.conf file and added this:

Code:

Section "Monitor"

    #UseModes    "Modes0" #monitor0usemodes

    Identifier    "Monitor0"

    VendorName    "Dell"

    ModelName          "D620"

    DisplaySize    432    270

    HorizSync      30.0 - 86.0

    VertRefresh    56.0 - 76.0

    ModeLine          "1440x900_60.00"  106.47 1440 1520 1672 1904  900 901 904 932 $

    #Option                "PreferredMode" "1440x900"

EndSection

Section "Screen"

    Identifier    "Screen0"

    Device        "Card0"

    Monitor        "Monitor0"

    Option        "IgnoreEDID" "TRUE"

    SubSection    "Display"

        Modes    "1680x1050" "1440x900" "1280x1024"

        Viewport    0 0

        #Modes      "1680x1050" "1600x1200" "1280x1024"

        Option        "IgnoreEDID" "TRUE"

    EndSubSection

EndSection

I didn't know what to put for my laptop's monitor information so I just made it up based on my laptop information assuming it wasn't important.

I restarted X11 and my resolut is still off, althrough now xrandr outputs this:

Code:

[~]$ xrandr

xrandr: Failed to get size of gamma for output default

Screen 0: minimum 640 x 480, current 1024 x 768, maximum 1024 x 768

default connected 1024x768+0+0 0mm x 0mm

  1024x768      76.0* 

  800x600        73.0  

  640x480        73.0

My bad - I did slightly alter the gtf output when placing it in my xorg.conf file.

In the "Screen" section, change the line

Code:

Modes "1680x1050" "1440x900" "1280x1024"

Code:

Modes "1440x900_60" "1280x1024"

We must use the same name for the mode that we used for the Modeline in the "Monitor" section, and you don't need/cant do 1680x1050.

I made said changes but it had no effect.

A frequent problem is that the HorizSync and VirtRefresh are too low. As long as you are using a LCD style monitor make the upper bounds something like 120.

You should be able to find your desired resolution in your Xorg.x.log file (though it might be rejected as being "xxx out of bounds", where xxx indicates one of horizontal sync or vertical refresh). I usually just up the HorizSync/VirtRefresh values until it works.

LCD monitors are not damaged by things out of bounds (CRT monitors can blow the flyback transformer, so don't do it on those).

Additional Erattum:

The

Code:

Option "IgnoreEDID" "TRUE"

lines should be deleted from your xorg.conf file. I inserted them because my monitor returns a bad EDID

I removed the line to no avail and there is no "out of bounds" message, but I did look for errors in that file and found this:

Code:

[    96.721] (EE) open /dev/fb0: No such device

[    98.380] (EE) PreInit returned 8 for "HDA Intel Headphone"

[    98.380] (EE) config/hal: NewInputDeviceRequest failed (8)