- Go System > Administration > Hardware Drivers
Then you will see that Ubuntu 9.4 recommends you to enable the NVIDIA driver (version 96).

- Enable it and wait for the installation.
- IMPORTANT! Before you restart your machine, you need another change not to have black screen on your next booting. This additional option is suggested at here and saves my months of sleepless night.
- Finally, restart your Ubuntu machine.
What is still missing.
Since now, the 3D accelerator seems working fine. You can see the small animation when you click any icon in the menu bar. However, when you enable the Visual Effects at System > Preference > Appearance, you lose the borders of all window. Does anybody fix this error?Posted by Minkee