solved - Ubuntu 10.04 screen resolutions

[marthter]

On 10-05-31 01:41 PM, D. Hugh Redelmeier wrote:
> | From: marthter<marthter-FFYn/CNdgSA at public.gmane.org>
>
> | The monitor is (quite old) ViewSonic P815
> | vertical frequency range 50 - 160 Hz
> | horizontal frequency range 30 - 115 kHz
>
> Is it so old that it doesnt' support DDC?
Yes and no, and I've tried it both ways with both the open and closed 
driver.  On the (on board) video card has only VGA output.  The monitor 
has a VGA input and a five-BNC-connector input (and I have both a 
VGA-to-VGA cable for the first case, and a VGA-to-5-BNC cable for the 
second case).  It claims in the manual to support DDC only when using 
the VGA input but I didn't get any output in Xorg.0.log similar to yours 
(mentioning DDC or EDID) with either cable.

> Have a look in your
> /var/log/Xorg.0.log to see what your driver finds.  For example,
> here's what mine finds.  It prints it 3 times (why?).  There are not
> many choices because an LCD really only wants one mode:
>
>      (II) RADEON(0): Port1:
>        XRANDR name: DVI-0
>        Connector: DVI-I
>        CRT1: INTERNAL_KLDSCP_DAC1
>        DFP2: INTERNAL_KLDSCP_LVTMA
>        DDC reg: 0x7e40
>      (II) RADEON(0): I2C device "DVI-1:E-EDID segment register" registered at address 0x60.
> ...
>      finished output detect: 1
>    

After suffering at low res for a few weeks (a little too busy to 
tinker), I took another stab at this...

The DDC comment was on the right track however.  I tried dozens of times 
to alter xorg.conf to tell it     HorizSync 30-115  Vertrefresh 50-160 
in the Monitor section.  Both with and without also specifying a 
ModeLine for 1920x1440.

In the tries where I gave a ModeLine, the log file was saying 'No valid 
modes for "1920x1440"; removing.' but gave no more info on how this was 
determined.

Eventually I found some post on how to turn up logging in xorg.  I 
couldn't find where is the "real" place to increase this logging so that 
it takes effect on a normal startup, but the fudged way I did it was to 
switch to the text console (Ctrl-Alt-F1), stop gdm with '/etc/init.d/gdm 
stop', then start X with 'startx -- -logverbose 6'.  This showed (among 
other things) the following very suspect lines in Xorg.0.log:

(II) NVIDIA(0): HorizSync : 28.000-55.000 kHz
(II) NVIDIA(0): VertRefresh : 43.000-72.000 Hz
(II) NVIDIA(0): (HorizSync from Conservative Defaults)
(II) NVIDIA(0): (VertRefresh from Conservative Defaults)

This eventually led me to a suggestion to just pick any resolution 
offered in the NVidia X Server Settings GUI, and to use the button which 
says "Save to X Configuration File".  This gave me a bigger xorg.conf 
file where the spot that needed changing was clear:


------------------------------------------------------------------
# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 1.0  (buildd at yellow)  Fri Apr  9 11:51:21 
UTC 2010

Section "ServerLayout"
     Identifier     "Layout0"
     Screen      0  "Screen0" 0 0
     InputDevice    "Keyboard0" "CoreKeyboard"
     InputDevice    "Mouse0" "CorePointer"
     Option         "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "InputDevice"
     # generated from default
     Identifier     "Mouse0"
     Driver         "mouse"
     Option         "Protocol" "auto"
     Option         "Device" "/dev/psaux"
     Option         "Emulate3Buttons" "no"
     Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
     # generated from default
     Identifier     "Keyboard0"
     Driver         "kbd"
EndSection

Section "Monitor"
     # HorizSync source: builtin, VertRefresh source: builtin
     Identifier     "Monitor0"
     VendorName     "Unknown"
     ModelName      "CRT-0"
#    HorizSync       28.0 - 55.0
#    VertRefresh     43.0 - 72.0
     HorizSync       30.0 - 115.0
     VertRefresh     50.0 - 160.0
     Option         "DPMS"
EndSection

Section "Device"
     Identifier     "Device0"
     Driver         "nvidia"
     VendorName     "NVIDIA Corporation"
     BoardName      "GeForce 6150SE nForce 430"
EndSection

Section "Screen"
     Identifier     "Screen0"
     Device         "Device0"
     Monitor        "Monitor0"
     DefaultDepth    24
     Option         "TwinView" "0"
     Option         "TwinViewXineramaInfoOrder" "CRT-0"
     Option         "metamodes" "1152x864 +0+0"
     SubSection     "Display"
         Depth       24
     EndSubSection
EndSection
------------------------------------------------------------------


(In the above I changed only the HorizSync and VertRefresh lines.)  On 
next startup, all the resolutions up to 2048x1536 were in the NVidia GUI 
as expected.  I'm not sure which of the additional options that the GUI 
added were the relevant ones for getting it to NOT ignore the HorizSync 
and VertRefresh (which I had already tried eight ways to Sunday).  But 
anyway it is working now in time for the round of 16 : - )

Thanks to all commenters.

Martin

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