AMD still hasn't caught up to Intel's 65nm "Kentsfield" processors in terms of overall performance or power efficiency, yet it has produced a credible alternative to those products. That fact, combined with aggressive pricing and the bold move of offering an unlocked upper multiplier on a $235 quad-core processor, has enabled the Phenom to grab our attention. We can finally say with confidence that if you have an existing Socket AM2 system and want to upgrade, buying a Phenom looks like a more attractive upgrade path than making the switch to Intel.

http://techreport.com/articles.x/14424