Laptops have the GPU integrated into the main board or on a small daughter board. If you need better graphics your best bet is to sell the laptop and purchase one with the graphics you need. I always recommend getting a laptop with some sort of dedicated graphics if there is any possibility of you using it for games or anything graphical.
A few years ago they did make an external adapter that used your PC card, but had poor performance. I think it was about $400 for the equivalent of a $50 video card in a PC. (or something in that ballpark)
Easy option, get a new laptop. Super Duper hard option, replace your laptop motherboard with a compatible model that has a better GPU, if possible, as well as the appropriate cooling system. Laptop mods are not for the squeamish, impatient, or those that don't have a steady hand with a soldering iron .