Hate to break this to ya...

But the GeForce 440 is for a DESKTOP PC, not a laptop.) Most of the time, the videocards in laptops aren't upgradeable as the GPU (Graphic Processing Unit) is integrated into the motherboard.
With a laptop, about the best you could expect would be to upgrade the drivers occaisionally.
If it's a "440 GO" videocard however, and the laptop is indeed upgradable (which would be REALLY RARE), then you'd probably have to crack the motherboard housing open with a screwdriver, and look for where it is upgradable. There should be a port where a similar card should be already installed...simply find where it's connected, disconnect it carefully, then perform the reverse for the installation of the new videocard.
The place where you'd want to get the drivers from would be:
http://www.nvidia.com