I’ve had to do this twice in the past week, so I thought I’d pass along how to do it. The majority of this was posted by some guy going by craigevil on some random linux board. Worked like a charm, thanks Craig.
1. Add the unstable repositories to your source list. Open your source list by running
sudo leafpad /etc/apt/sou*
and then add
2. run the following in order
apt-get -t unstable install nvidia-kernel-source
m-a a-i nvidia-kernel-source
apt-get -t unstable install nvidia-glx
apt-get install nvidia-xconfig
3. Open your source list again, and comment out the unstable repositories
otherwise the next time you run an update, you might upgrade from Squeeze to Sid. Reboot, and you’re done (hopefully).