I'm guessing the PathPilot image probably doesn't have the Nvidia drivers installed. You could either install Nvidia drivers or use onboard video (if you have it).
I believe this is the correct driver (please double check): NVIDIA DRIVERS Linux x64 (AMD64/EM64T) Display Driver
You can also try installing the nvidia drivers with apt-get, however, the binaries from Nvidia have worked fine for me in the past on Ubuntu (I have not tested accelerated graphics under Ubuntu 10 specifically though).
Good luck!