People that need some help to compile a new PC may want to check out the new ARS system guide at ARS Technica. In their October 2009 edition they offer advice on building a $600 to $800 budget box, a $1,400 to $1,600 hot rod and a $8,000 to $10,000 god box.
The Budget Box: The The Budget Box falls within the $600 to $800 range, and is aimed at getting you the most bang for your buck. While we aim for maximum value, this build is typically gaming-friendly, especially if you're not intent on pushing it too hard with the latest and greatest.
The Hot Rod: This is our mid-tier system, and it falls somewhere between $1,400 and $1,600. Maximum gaming value is one of the The Hot Rod's main goals, but it's also suitable for media work and other duties.
The God Box: If you're one of the blessed few who can afford to spend between $8,000 and $10,000 on a system, then the The God Box is for you. But because gluttony is a sin, some prefer to just pick a few parts from this when they're looking to give their Hot Rod a boost.