You need to get a notebook with dedicated video RAM for games and more intensive programs like Autocad. This means a dedicated video card with its own memory independent of the system RAM (shared or integrated RAM uses system RAM and doesn't cut it for intensive uses.

You need to specify more of your specifications such as whether a desktop replacement is acceptable for your use or whether battery life, weight, LCD size, and other factors are important.

You candidates are Pentium 4M for destop replacement, Pentium M (Centrino) for best combination of weight, battery life, and wi-fi performance or AMD 64 for the best option for the future (64bit Longhorn operating system). Or, of course, you have the Apple option if it fits your pricing and performance requirements.