Elite Bastards posted an update regarding AMD's Barcelona architecture

Although Barcelona is still based around the same K8 core that graced AMD's Athlon64 series of CPUs and the like, there are still a myriad of changes that have been made to these new parts, as highlighted above. Let's take this opportunity to take a look through them all to give us an idea of just what AMD have done to improve the performance and efficiency of Barcelona over its predecessors.

AMD's Barcelona architecture - July update