DDR3 vs. DDR2 and laptop video cards

Sorry if the inclusion of video cards in this question goes against forum rules. This is primarily a memory question but there's a reason for dragging video cards into this.

I'm putting together the final specs on a new HP HDX18t and I'm deciding between getting:

4GB of DDR2 memory with the required 512MB NVIDIA GeForce 9600M GT - For DDR2

-OR-

4GB of DDR3 memory with the required 1GB Nvidia GeForce GT 130M - For DDR3 Memory

I don't plan on overclocking this laptop and I don't plan on gaming with this system, but I am looking for a desktop replacement and I will be running processor/memory intensive programs. Will the DDR3 at normal clock rates be appreciably faster than the DDR2? Is there any other good reason I should choose one over the other?

Any and all advice is greatly appreciated.

Regards,
Jim

What you said seems consistent with the conventional wisdom I've heard. Aside from the obvious 1GB versus 512MB difference in video cards, do you think there is any performance benefit for one video card using the higher clock rate DDR3 versus the card leaning on the DDR2? Will that even matter?

Thanks again,
Jim

Thank you for the help. Much appreciated.

This is for jdw5155. Before you buy this box from HP, you need to check nvlddmkm.sys BSOD. Just look it up on google and you will see there is some sort of conflict between microsoft, nvidia, and HP, that has never been resolved and there is no solution. My laptop lasted 14 months and totally crashed. The battery lasted the same amount of time, and they cost $120. These people put out a trash product. You should consider other OEMs.