In this article, you will find a comparison of the latest Xeon (Irwindale), the previous Xeon (Nocona), the old Xeon (Galatin), the Dual core Opteron, and the "normal" Opteron, of course. We also included the Pentium-D to get an idea of what a Dual core Xeon could do, although the comparison is not completely fair: the memory subsystem of a Dual core Xeon will have higher latency and slightly lower bandwidth as it will use ECC buffered DIMMs instead of non-buffered DIMMs.

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