The x700 is a lot better then the x1400, it's a good ATI laptop card, the model better then it is the x1600. Second is the 9700 and third is the x1400.
If you add in the other three cards then I dont know. I'm pretty sure the 7800 is the best for laptops (expensive though), not sure if the 6800 beats the x1600. I'd go with an x700 myself since the prices on laptops with the better cards is generally a lot more. You can get laptops with x700 in them for about 1200.