Looking to buy/build a rock solid SW laptop

I'm surprised everyday that my current laptop can even run SolidWorks. It's a Dell Latitude D630 running a centrino duo @ 2.1 Ghz. 2 Gb of RAM. Intel 965 integrated graphics. I'm new to SW. Been teaching myself over the last six months or so. At first I thought my machine was up to the task but as I learn how to use the program more and get into more complex and larger assemblies my computer crashes, SW takes forever to highlight features. Just all the stuff that happens with a substandard machine trying to handle something it was never intended for lol. So I want to either purchase a specifically tailiored laptop that will allow me to continue to learn this program or I was looking at gaming tailored rigs like AlienWare by Dell. I understand that a laptop like this will cost a "little" more than this centrino I bought back in 2008. I expect between 1,500-2,000. I'm looking for suggestions from users who actually use this program on a daily basis about CPU,ram,gpu. OS will be win7 bc I hate win8. Thanks everyone.

SolidworksGeneral