If you need it to be under 7lbs (the standard for what you want), you should go with the Sonoma platform, but wait until the PCI-Express X16 bus is incorporated into current models. For example, the Dell 6000 will add that functionality. With PCI-X, you'll have the video power you need.
And with CAD and 3d modeling, you'll want a new laptop in 2 years anyway, when Longhorn 64 comes out.
I'm looking into buying a new laptop to use for architectural drafting and modeling, but I'm having difficulty finding one where I'm not comprimising something. As I understand it, it needs to have a graphics card with at least 128mb of non-integrated RAM, a high quality screen that is at least 14", preferably a gig of RAM, plenty of hard drive space, and preferably something that doesn't way more than 6 lbs. Also, I'm wondering if it is worth it to buy a 64 bit processor from the limited options out there now, or get a very good 32 bit processor even though everything will be 64 bit in a year or so. The models I've been looking at for 64 bit are HP and Compaq, but they are very heavy. Are there others I should be aware of? For 32 bit I'm looking at IBM T42 (but I've heard the screen quality is sketchy) and Toshiba Satellite M35. Any info, recommendations, warnings would be appreciated!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic