Ubuntu Hoary: GeForce FX 5200 Ultra Dual Display

Install the latest NVidia driver:

sudo apt-get install nvidia-glx
sudo nvidia-glx-config enable
sudo apt-get install nvidia-settings

Modify xorg.conf. See the txt file.

Reference:
http://www.ubuntulinux.org/wiki/BinaryDriverHowto
http://www.ubuntulinux.org/wiki/XineramaMultipleMonitors