Build a Silent PC updated their Build a Silent PC Guide for 2008.
A quote from the article:
>> Build a Silent PC Guide updated for 2008
We have been running the guide since 2003, recommending various silent PC components over the years. Everything from silent CPU coolers to silent video card coolers are covered. We have updated the guide to include advice on how to cool quad-core processors while generating less than 18 dBA of sound.
>> Build a Silent PC Guide updated for 2008