$ dpkg -l|egrep -i 'libcuda|bumblebee|prime|nouveau'
ii  libdrm-nouveau2:amd64                           2.4.76-1                                    amd64        Userspace interface to nouveau-specific kernel DRM services -- runtime
ii  libdrm-nouveau2:i386                            2.4.76-1                                    i386         Userspace interface to nouveau-specific kernel DRM services -- runtime
ii  xserver-xorg-video-nouveau                      1:1.0.14-0ubuntu1                           amd64        X.Org X server -- Nouveau display driver