Bang for Buck:
Of course we have to check how the performance of all configurations is. As usual AMD leads with the best bang for your buck but at the cost of much higher power-consumption under load. If you don't need that much power you will do fine even with an AMD CPU. The sad part is, besides Windows 7 and some other applications not many software vendors go the extra length to optimize for AMD.
Even under overclocked situations AMD still leads, but at the cost of much higher power-consumption. We did not include ASRock and Elitegroup in the comparsion, because they are not targeting the high-end market. Also during overclocking CPU temperatures are higher. The MSI P55-GD80 and Intel DP55KG are much more expensive and do not offer anything substantial compared to the MSI P55-GD65.