Budget System Building Guide
 

For that very reason, we started writing these System Buying Guides a few years back. We have three categories of Buying Guides: Budget, Mainstream and Performance. Our Budget Guide has a spending limit of $600, the Mainstream limit is $1,200 and we allocate $2,400 for our Performance Guide. The systems that we piece together here are designed to give you the best overall experience under the given budget. Obviously, if you are a gamer, you would probably want to spend more money on a video card than other components. Our guides are designed with overclocking in mind, so we often select lower-end processors / memory / video cards to save money, because we know these can be overclocked to equal or outperform higher priced hardware. All of our guides exclude common components such as a mouse, keyboard, monitor, OS, etc., under the assumption that you already own these items.

http://www.ocia.net/articles/budget2008/page1.shtml