I'm not building a Dell... o.O
I decided to because I really want a laptop with out all the brand-name crap. No pre-loaded junk, no brand name labels, and a fast laptop for half the price.
The one I'm going to build is equivelent to a $3000 from Toshiba. What does it cost me? About $1600
The Pentium M uses Socket 479 and the Turion uses Socket 754, I believe. Good luck in finding the Turion though...it's pretty much impossible to find a boxed version for retail. You can't just buy a normal motherboard for a laptop. Laptop motherboards are designed to be compact, so the insertion of things is different. The graphics accelerator is usually integrated (although nVIDIA came up with the in-genius udea of the MXM, short for Mobile PCI-Express Modules).