Comment 32 for bug 164589

EzNet:

I've noted some differences between your config and mine.

1) The file nvidia-kernel-nck:
    - You use the 169.12 driver, so it os the nvidia-new driver, it must be specified correctly.
    - You must tell the driver it is a mobile card, if not the PerfLevelSrc may not work.
    - So you must have these lines (and I only have these two, not three like you):
        alias char-major-195* nvidia
        options nvidia_new NVreg_Mobile=1 NVreg_RegistryDwords="PerfLevelSrc=0x2222"

2) The location of nvidia-kernel-nck:
   - You may have (like me) two versions of this file. One in /etc/modprobe.d/ and another in /etc/modutils/
   - The file in /etc/modprobe.d must be the one that applies when the driver is loaded and is the file we talk about.
   - The file in /etc/modutils/ must contain only next line:
       alias char-major-195 nvidia

3) Your xorg.conf file is a bit strange:
   - It contains 2 "Device" sections, it is not needed the first one.
   - You have two screens configured, but both TwinView and Xinerama deactivated.
   - The best solution I've found to work with 2 screens at a time is using TwinView, and configure only 1 screen, then when I start a session and the second monitor is detected, if the driver sets incorrectly the resolution then I use the nvidia-settings application to change resolutions and so on.
   - NEVER use the screen resolution shipped with Ubuntu with an Nvidia card! It breaks the xorg.conf easily.
   - This is my "Screen" section, for reference:
       Section "Screen"
          Identifier "Screen0"
          Device "Videocard0"
          Monitor "Monitor0"
          DefaultDepth 24
          Option "NoLogo" "True"
          Option "DynamicTwinView" "True"
          Option "RenderAccel" "True"
          Option "TwinView" "True"
          Option "MetaModes" "nvidia-auto-select, nvidia-auto-select"
          Option "TwinViewXineramaInfoOrder" "DFP,CRT"
          Option "NvAGP" "1"
          Option "Coolbits" "1"
          SubSection "Display"
              Depth 24
          EndSubSection
       EndSection

   - Things to note:
       * Using NvAGP instead of AGPGart, but it is a personal preference.
       * Enabling Twinview

I hope this info can help you a bit.