Yes, but the cost and practicality usually steer most folks away from doing this. Only certain brands/designs of laptop offer such a capability and it'll require a specialized port like Suprfire pointed out. Laptops are laptops for a reason. If you want high end GPU performance, I'd recommend investing in a PC to house that GPU as well. But hey, that's just me. Frankensteining a GPU in a separate box to a laptop is like buying a sidecar for your motorcycle. Ya, it'll carry two people now, but there's this invention called a "car" that does the job so much better.
Laptops automatically turn into dinosaurs at the 5 year point. Just simply no way to really upgrade something that old, and the vast majority of laptops typicallly aren't upgradeable when it comes to the CPU/GPU. So the answer would be no in your case. Time for a new laptop or a new PC I'd say if your are sniffing after more GPU power.