We do our best to consider all the options, but the simple truth is that without spending numerous pages on each Buyer's Guide, we can't explain every facet about each pick. There are always alternatives to the choices that we make, and you can substitute parts as you see fit. If you don't like our motherboard, or you want a slightly faster (or slower) CPU, GPU, etc., then you can make that change. The overall goal of the System Buyer's Guides is to provide a complete recommendation for every component needed to build a new computer. Some parts are very personal selections, and we won't dwell too long on those choices. If you have a set of speakers or a display that you prefer over our pick, by all means, go with what you like. However, if you're overwhelmed by the number of decisions that need to be made, picking up the exact choices listed in our Guides should give you a reliable computer that anyone would be happy to own.
http://anandtech.com/guides/showdoc.aspx?i=2535&p=1
Mid-Range Buyer's Guide
Mid-Range Buyer's Guide 
