I have been actively using SolidWorks for about 9 months and need to spec a new laptop. I run SolidWorks 2010 on a Dell Presion T3400 with 3.0GHz Core Duo (E6850) processor, NVIDIA FX 1700 Grahpics Card and 8GB RAM but have a need for a laptop for out of office design reviews and some site based work. The laptop will not be required for rendering or FEA type work but will need to handle the display and modeling of large assemblies (5000+ components). From browsing these forums, it appears that a Duo Core processor may give me similar proformance to a Quad Core processor as this type of work is largely single threaded.

Would the i7-620M (2.66GHz, 2 Core, 800/1066MHz menory) give better performance then the i7-820QM (1.73GHz, 4 Core,1066/1333MHz menory)?  (i.e. is the higher processor speed of the 620M of more value than the higher RAM speed of the 820QM?) Any other suggestions?

How significant is the graphics card for this type of work? Would I see a significant performance improvment between the NVIDIA Quadro FX 2800M and FX 3800M cards?