Some Dells have an external GPU option. But that's pretty rare so for all others, no.
However if you want to watch a 3D movie you could try a 3D TV then the usual 3D video player.
That is, 3D is not just the GPU but the display so I really should just write no and no and no.
I have a gaming laptop which has a onboard Intel GPU and a nvidia GPU. The onboard GPU prevents nvidia from giving me full GPU options(including stereoscopic 3d options.)
Is there another way for me to get stereoscopic 3d?