I don't know. Depends on what mods you are planning to install, Earthlinger. My friend from Ukraine has a dual core overclocked at 4.2Ghz with 3GB GTX 580 and when installing only Pelagiad Expanded and nothing else, his frame rate dropped to 12-15. So add MGE XE and shadows and graphics enhancers and the frame rate is even lower.
Then there was a time last year when I asked someone on these forums for their frame rate with the Tamriel-Rebuilt maps added and MGE XE enabled. The person levitated extremely high straight up into the air so as to see the entire land mass of Vvardenfell and the mainland. His frame rate was about 2 seconds per frame, or 0.5 frames per second. I forget what his computer specifications are but they were decent from what I recall. As you can see, you need a CPU with lots of raw processing power to run a heavily-modded Morrowind, at least until OpenMW or Project Aedra are completed. Vanilla Morrowind will run perfectly fine on a computer from 10 years ago.
I, as well, play Morrowind on a laptop; not currently, though. Have you seen the Sager laptops by Xoticpc? They have the http://www.xoticpc.com/sager-np9270-clevo-p270wm-ships-early-march-p-3595.html?wconfigure=yes laptop which has an i7-3960X at 3.3-3.9GHz stock clock speed and dual GTX 580M SLI. I personally am waiting for the Alienware M18xR2.
Is your laptop one that you're planning to buy or one that you own?