xenoael check /var/log/messages or other files there for strange errors.
casb I'm not sure on what distro you are. Most distro's like Mandrake and Redhat use a file called modules.conf. (not all distro's default to it) To that you should add a line:
alias char-major-195 NVdriver
Then it will be loaded on startup. Debian uses "/etc/modules" which works a little different.