X.org for Sharp Aquos and nVidia 8800 GTS

Configuring X for functionality with an HDTV and any nVidia card is quite a frustrating adventure. This is the procedure I took to configure X for my nVidia 8800 GTS ( g80 ) connected to my Sharp Aquos LC-32GP1U through DVI-D. This Aquos is a 1080p monitor, so I am configuring it to run at 1920x1080.

When I first start X, I get a display. The resolution is only 1280x1024. So the first step is to see what X's problem is. The easiest way is to first enter runlevel 3 and start X from there with added switches for verbosity.

Use Ctrl+Alt+F1 to switch to the first virtual terminal.
Login and run telinit 3 to enter runlevel 3.
Start X with startx -- -verbose 6 --logverbose 6 2> /tmp/startx.log
As soon as X displays the screen, press Ctrl+Alt+Backspace to kill X.

Now, we look at /tmp/startx.log. We are looking for the mode validation checking for possible resolutions, specifically 1920x1080. In this output, X tells us that 1920x1080 is to large for DFP, which it isn't because this is a 1080p monitor. We need to tell X to not worry about DFP. Insert the following line in the Device section:

Option "ModeValidation" "NoDFPNativeResolutionCheck"

Now start X with startx -- -verbose 6 --logverbose 6 2> /tmp/startx.log. We'll see nothing has changed. Kill X and look at /tmp/startx.log. Look at the mode validation. X is now complaining about timings. We need to tell X to use exact timings, which we do by adding this line to our Device section:

Option "ExactModeTimingsDVI" "True"

Now start X with startx -- -verbose 6 --logverbose 6 2> /tmp/startx.log. We'll see that the screen is deformed. Kill X and look at /tmp/startx.log. Nothing will scream out the problem unfortunately. The resolution is actually correct, 1920x1080. However, the image is not correctly scaled. It took me many frustrating google searches to find a solution for this. We need to add this line to our Device section to have the video card use the monitor's native scaling.

Option "FlatPanelProperties" "Scaling=Native"

Start X and voila. Beautiful 1080p resolution, perfectly scaled. Here is the entire /etc/X11/xorg.conf from my machine:


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

Section "Files"
ModulePath "/usr/lib64/xorg/modules/extensions/nvidia"
ModulePath "/usr/lib64/xorg/modules"
EndSection

Section "ServerFlags"
Option "AIGLX" "on"
EndSection

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

Section "Monitor"
Identifier "Monitor0"
EndSection

Section "Device"
Identifier "Videocard0"
Driver "nvidia"
Option "ExactModeTimingsDVI" "True"
Option "ModeValidation" "NoDFPNativeResolutionCheck"
Option "FlatPanelProperties" "Scaling=Native"
Option "AddARGBGLXVisuals" "True"
Option "DisableGLXRootClipping" "True"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1920x1080"
EndSubSection
EndSection

Section "Extensions"
Option "Composite" "Enable"
EndSection