add repo:
deb
http://nvidia.limitless.lupine.me.uk/ubuntu edgy stable
wget -O- --quiet
http://nvidia.limitless.lupine.me.uk/ub ... .me.uk.gpg | sudo apt-key add -
then install nvidia-glx in synaptic
open terminal
type commands:
nvidia-xconfig
nvidia-xconfig --composite
nvidia-xconfig --allow-glx-with-composite
nvidia-xconfig --render-accel
nvidia-xconfig --add-argb-glx-visuals
then type sudo gedit /etc/X11/xorg.conf
scroll down and replace 16 with 24 where it says default depth under "Screen" section
Restart Xorg and it should work. At least it did for me with a Geforce Go 7400)