The GT440 is not on the list of the supported graphics, on the nvidia download site.
If you take a look at the supported products tab, it is not in the list.
Some had limited success, because their cards were detected as GT435, but i have read on other forums, that the performance is quite limited compared to the performance on the same machine under windows.
I'm running ubuntu 10.10, 64 bit, and so far, had no success in running X with the offical ubuntu nvidia packages. The next step is the manual install from the official nvidia installer.
I'll update you if that worked.