Now, do you get display or not?



if you have correctly installed the drivers then do

Code:

sudo nvidia-xconfig

this will create a new config file, after that restart X (GUI).



and then check if driver is enabled correctly or not.

Code:

glxinfo | grep endering

It should say YES. if it says no, then please come and post the output of

Code:

cat /var/log/Xorg.0.log

Note: X is short for X server which is responsible for GUI display in Ubuntu and other *nix based oses

I would assume 9800GT was not released and hence not supported by the restricted drivers available in 8.04.



The easy way is to install via Hardware Drivers. If you want to load the newer version you can add this PPA and enable the 190 series. It will download and do the rest



Before the you do the above steps make sure ur system is updated just to ensure there are no bugs killing your installation.



Other way as suggested by Gaurish. My personal preference is via ppa/Jockey as it saves me the time to recompile nvidia header every time the kernel is updated.

Yes, do as @archish says, install the latest nvidia driver first and generate a new config with nvidia-xconfig