Xorg Configuration for Unregistered Resolution

Felix Miata mrmazda at earthlink.net
Sun Jan 26 10:04:06 PST 2014

On 2014-01-26 07:45 (GMT+0330) kraxadmin composed:

> I have a monitor with native resolution of 1600*900_60.00, and the intel on
> board Gen3 Xeon video chipset (i915).
> when i do $> xrandr the 1600x900 resolution is not in the list. I tried to
> write an xorg configuration for monitor and I placed it on
> /etc/X11/xorg.conf.d/10-monitor. but i must mess some value in there up;
> that it ha no effect and doesn't change the resolution.
> I am sure the /etc/X11/xorg.conf.d/10-monitor is being read at $>
> startx because
> if i put anything wrong like ()*! at that file *X* won't start and produce
> an error.
> The cvt 1600 900 returns:

> 1600x900 59.95 Hz (CVT 1.44M9) hsync: 55.99 kHz; pclk: 118.25 MHz
> Modeline "1600x900_60.00"  118.25  1600 1696 1856 2112  900 903 908
> 934 -hsync +vsync

I've never ever found it necessary to add any modeline to an Xorg config 
file, regardless of driver, and regardless of hardware. When either EDID is 
valid, or the config file(s) is/are valid and include HorizSync, VertRefresh 
and PreferredMode, Xorg calculates an appropriate modeline automatically. 
IOW, Xorg automatically does the same thing gtf and xvt do when a valid 
config file or files include(s) HorizSync, VertRefresh and PreferredMode. 
Apparently your display has invalid EDID and needs a validly constructed 
xorg.conf or suite of 3 files in xorg.conf.d/.

> And this is my 10-monitor.config file:

10-monitor.config is not a valid standard filename for Xorg to use automatically.

> Section "Device"
> Identifier  "Intel i915"
>    Option   "VGA1" #"VGA screen"
>    Driver      "intel"
> EndSection
> Section "Monitor"
>    Identifier  "Primary Monitor"
>    Modeline    "1600x900_60.00" 118.25 1600 1696 1856 2112  900 903 908
> 934 -Hsync +Vsync
>    Option      "PreferredMode" "1600x900"
> EndSection
> Section "Screen"
>       Identifier    "Screen0"
>       Device        "VGA1"
>       DefaultDepth  24
>       SubSection "Display"
>       Depth        24
>       Modes   "1600x900_60.00"
> EndSubSection
> EndSection

I've never found configuring a monitor alone sufficient. It needs to be 
coupled to a display and a device in separate files in /etc/X11/xorg.conf.d/. 
The format you have made needs to be in /etc/X11/xorg.conf. See 
http://fm.no-ip.com/Share/xorg.conf-minimal-EDID-workaround as example of 
what I mean by coupling in xorg.conf.d/.
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)

  Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

Felix Miata  ***  http://fm.no-ip.com/

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