MY COMPUTER
dpkg -l | grep nvidia

rc  nvidia-glx                                 1.0.9631+2.6.20.5-15.20                NVIDIA binary XFree86 4.x/X.Org driver
ii  nvidia-glx-legacy                          1.0.7184+2.6.20.5-15.20                NVIDIA binary XFree86 4.x/X.Org 'legacy' dri
ii  nvidia-kernel-common                       20051028+1ubuntu7                      NVIDIA binary kernel module common files
--------------------------------------------------------------------------------------------------------------------woody@Laptop-123:~$ 

NEIGHBOR's COMPUTER
dpkg -l | grep nvidia

ii  nvidia-glx                                 1.0.9631+2.6.20.5-15.20                NVIDIA binary XFree86 4.x/X.Org driver
rc  nvidia-glx-legacy                          1.0.7184+2.6.20.5-15.20                NVIDIA binary XFree86 4.x/X.Org 'legacy' dri
ii  nvidia-kernel-common                       20051028+1ubuntu7                      NVIDIA binary kernel module common files