Die Hinweise (wichtig!) lesen und ein geeignetes Repository hinzufügen:
sudo add-apt-repository ppa:xorg-edgers/ppa

Paketlisten aktualisieren
sudo apt-get update

Nachsehen, welche Pakete zu Nvidia zur Verfügung stehen
sudo apt-cache search nvidia

Hier beispielsweise:
(...)
nvidia-310 - Transitional package for nvidia-310
nvidia-310-dev - Transitional package for nvidia-310-dev
nvidia-settings-310 - Transitional package for nvidia-settings-310
nvidia-319 - Transitional package for nvidia-319
nvidia-319-dev - Transitional package for nvidia-319-dev
nvidia-settings-319 - Transitional package for nvidia-settings-319
nvidia-persistenced - Load the NVIDIA kernel driver and create device files
nvidia-settings-325 - Tool for configuring the NVIDIA graphics driver
nvidia-325 - NVIDIA binary Xorg driver, kernel module and VDPAU library
nvidia-325-dev - NVIDIA binary Xorg driver development files
(...)

nvidia-325 ist das Gewünschte:
sudo apt-get install nvidia-325

Done!