Mainstream System Buying Guide @ OCIA.net
 

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/mainstream/page1.shtml