The models in question are GF 610M (and entry level card) and 285M (an older, but much beefier card). All I'd like to do is swap them. The Internet is not very generous on particulars regarding this kind of information.

Has anyone had experience with this or can anyone say if the idea is conceptually sound. The 610M laptop is under warranty and I'd prefer not to pry it open before I'm sure the warranty is worth voiding.

Find the drivers for the older card, and install them. Than pry open your laptop to see if the ribbon cable attaching the current graphics card will attach to the older one. Next check if the older card will actually fit in the laptop in question, and if the wiring is the same ( power supplies ).

If you are sure of things, swap the cards, making darn sure not to damage the ribbon cable ( it is fragile ).
While still dissembled, fire up the laptop to see if it worked.
If it starts beeping at you, and has no display, swap the cards back,

I've neverpermanently damaged a laptop swapping out graphics cards, however some folks have, so do it at your own risk.

Bah, after some thorough digging it appears the 610M machine isn't MXM-enabled, which means the GPU is VERY likely integrated. Thanks for the reply, though!