Karmic, color depth, and all that.

[BioTronic]

Greetings. I am running Karmic Koala on a Dell Precision M90, and have some problems with my color depth, or at least that's what I believe.

I have googled this problem numerous times, reading a lot about /etc/X11/xorg.conf, and have created numerous files in that location, with all manners of (probably) valid contents. I have yet to try invalid contents, in the hope that Linux is reading the file, and doing so would crash the system.

This is my current xorg.conf, after many iterations:

Section "ServerLayout"
Identifier "X.org Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection

Section "Files"
ModulePath "/usr/lib/xorg/modules"
FontPath "/usr/share/fonts/X11/misc"
FontPath "/usr/share/fonts/X11/cyrillic"
FontPath "/usr/share/fonts/X11/100dpi/:unscaled"
FontPath "/usr/share/fonts/X11/75dpi/:unscaled"
FontPath "/usr/share/fonts/X11/Type1"
FontPath "/usr/share/fonts/X11/100dpi"
FontPath "/usr/share/fonts/X11/75dpi"
FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
FontPath "built-ins"
EndSection

Section "Module"
Load "record"
Load "extmod"
Load "glx"
Load "dri2"
Load "dri"
Load "dbe"
EndSection

Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
EndSection

Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5 6 7"
EndSection

Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
EndSection

Section "Device"
### Available Driver options are:-
### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
### [arg]: arg optional
#Option "SWcursor" # [<bool>]
#Option "HWcursor" # [<bool>]
#Option "NoAccel" # [<bool>]
#Option "ShadowFB" # [<bool>]
#Option "UseFBDev" # [<bool>]
#Option "Rotate" # [<str>]
#Option "VideoKey" # <i>
#Option "FlatPanel" # [<bool>]
#Option "FPDither" # [<bool>]
#Option "CrtcNumber" # <i>
#Option "FPScale" # [<bool>]
#Option "FPTweak" # <i>
#Option "DualHead" # [<bool>]
Identifier "Card0"
Driver "nv"
VendorName "nVidia Corporation"
BoardName "G71GL [Quadro FX 3500]"
BusID "PCI:1:0:0"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
SubSection "Display"
Viewport 0 0
Depth 1
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 4
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 8
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 15
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 16
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection


Now, is there some other place to change this? Am I doing this right? Should I sacrifice more virgins to Cthulhu, or is Hastur the one to ask in these situations?

[asmoore82]

googling "xorg.conf" will more than likely yield out-dated results.

Modern *buntus should be able to run 100% functional with no "xorg.conf" at all.

What is your original "possibly color-depth" problem?

You might want to go ahead an check/post the output of
xrandr

[BioTronic]

googling "xorg.conf" will more than likely yield out-dated results.

Modern *buntus should be able to run 100% functional with no "xorg.conf" at all.

What is your original "possibly color-depth" problem?

You might want to go ahead an check/post the output of
xrandr

Sorry, I forgot including the actual problem. :p It seems I'm running in 16-bit colors, and I want 24-bit.

xrandr output:

Screen 0: minimum 640 x 480, current 1920 x 1200, maximum 1920 x 1200
default connected 1920x1200+0+0 0mm x 0mm
1920x1200 60.0*
1680x1050 60.0
1400x1050 60.0
1280x1024 60.0
1440x900 60.0
1280x960 60.0
1360x768 60.0
1152x864 60.0
1024x768 60.0
800x600 60.0 56.0
640x480 60.0

[asmoore82]

could you check this

cat /var/log/Xorg.0.log | grep -i depth
or maybe just post the whole log if that doesn't say anything

[BioTronic]

Right. Output:

(==) NV(0): Depth 24, (--) framebuffer bpp 32
(--) Depth 24 pixmap format is 32 bpp

it seems to me it is running in 24-bit. Still, image quality seems to indicate otherwise, compared to my friend running a very similar setup on a machine of the same make and model. Specifically, a rendered sphere has obvious 'banding' of colors on my screen, none on his. Same drivers, same Ubuntu version. Only thing I can remember being different is his is installed on his NTFS Windows 7 partition.

[marek.]

Right. Output:

(==) NV(0): Depth 24, (--) framebuffer bpp 32
(--) Depth 24 pixmap format is 32 bppit seems to me it is running in 24-bit. Still, image quality seems to indicate otherwise, compared to my friend running a very similar setup on a machine of the same make and model. Specifically, a rendered sphere has obvious 'banding' of colors on my screen, none on his. Same drivers, same Ubuntu version. Only thing I can remember being different is his is installed on his NTFS Windows 7 partition.


Hey, I have solution for you.
I have Dell m90 also, and I had exactly same issue as you with nv xorg driver.
What you need to do is to add:

Option "FPDither" "1"

to you "Device" section.

Good luck! ;)