Loadable kernel modules in Linux are loaded (and unloaded) by the modprobe command. They are located in
/lib/modules and have had the extension .ko ("kernel object") since version 2.6 (previous versions used the .o extension). Often when you update your kernel and have compiled your own drivers in previous kernels you must compile them again. If binaries were obtained through pre-compiled such as deb Debian packages which are handled via dpkg through package managers such as apt/aptitude or if your distribution is another flavor of Linux such as RHEL then BRPM's or RPM Package Manager sometimes known as RedHat Package Manager.
Depending on your distribution an attempt to load either drivers with "
modprobe [options] [-i] [-b] modulename" or in your case "
modprobe nouveau" | "
modprobe nvidia" | "
modprobe nv" if they exists and if they are located in the corresponding location for your distribution. Ubuntu is based off of Debian and it may be assumed packages are most likley handled through dpkg managers on your system if its what these forums are designated for.
If your problem still exists, perhaps shed more light on the issue by including these outputs:
If possible please include information on your kernel objects by attempting:
Did you compile bumblebee & your NVIDIA driver from source or did you use a pre-compiled package? If they were compiled by you what versions did you use? If you installed the pre-compiled packages please provide the exact versions.