I just upgraded to Ubuntu 10.04 Lucid Lynx. I liked 10.04 more than previous versions. Anyway here i’l guide how to install drivers manually for your nvidia card on Ubuntu 10.04. I have intel machine with Nvidia 9500 GT card.

While installing Nvidia Driver for my card i faced two primary problems:
1) I need To Stop/Kill X SERVER. (I didn’t know howto at the time)
2) I need to uninstall Nouveau because it stopped my installation (I didn’t know howto at   the time lol)
( Noveau is a new open-source driver with 3D acceleration for NVIDIA cards that ships with Ubuntu 10.04. )

So First Step of Installation: Download the Nvidia Driver for your card from Nvidia official site.

i had downloaded the driver into /home/padam/Downloads (here padam is my username on ubuntu).

Second, when i ran nvidia driver setup sh file after just killing X SERVER, then during the installation an error came saying Nouveau must be removed. So my installation was cancelled. I had to remove nouveau from my system. Here is the command to remove nouveau :
sudo apt-get –purge remove xserver-xorg-video-nouveau

Third, Now to install driver i had to stop/kill the X SERVER. so to kill it i opened the terminal, typed this command: sudo /etc/init.d/gdm stop
That did it. after executing that command on terminal window, i killed X and gets a command prompt/terminal type full screen :D.
Okie i also want to tell that i re-installed the driver, just to write down the steps for tutorial hehe :D. So during re-installation when i tried to killed X server by executing above command, i got the orange color screen with UBUNTU written at the center and few dots below that, and i waited for few minutes, nothing happened. So i just did this: CTRL + ALT + F1 yeah i pressed those keys and viola i got command prompt/terminal type full screen. so if u face this problem then u know how to deal with it.
But this command  sudo /etc/init.d/gdm stop is necessary/must/compulsory to kill X SERVER.

So here are the above steps that must be done to install nvidia drivers: remove nouveau first from system, then Kill the X SERVER.

After killing X SERVER, you get a command prompt/terminal type Full screen. So use a cd command and navigate to the location where nvidia driver setup file is present. In my case my location was /home/padam/Downloads

so i typed /home/padam/Downloads and pressed Enter.

Name of my nvidia driver setup  file was NVIDIA-Linux-x86-256.44.run. Now i ran a driver setup file using this command:
sudo sh NVIDIA-LINUX-x86-256.44.run -k $(uname -r)

And after that setup runs, then follow the instructions and your driver will be installed.

Note: i also ran the file using just this command: sudo sh NVIDIA-LINUX-x86-256.44.run This works and driver was installed but there was a default. When i applyed screen resolution of my screen to 1024 * 768 then it didn’t worked properly, there was wide black space at the left of my screen.

When installation get complete, you are returned to same command prompt/terminal type screen. Now execute this command to start X SERVER back:
sudo /etc/init.d/gdm start
This will start the X SERVER and you gets the old UBUNTU LOGIN SCREEN. You better restart the computer then, it would be better. So after restart, You are done. You can check the Nvidia settings by going at System -> Preferences -> NVIDIA X Server Settings.

So this is it. This is how i installed my nvidia driver for my Nvidia 9500 GT. I hope this also works for you.