Q:
A: Core 2 Extreme may be the best performer but usually not the best bang for your buck. http://www.techreport.com/articles.x/14756/10 A fast clocked Core 2 Duo (3.0gHz or higher) is pretty good (and energy efficient) except in heavily multi-threaded apps or symmetric multi-processing where quads would be best. The cheap, moderately clocked Q6600 get quite awesome when overclocked to 3.0gHz or higher level.