Insufficient clock-speeds of Bulldozer are probably the reason why AMD now claims that the 16-core offering will be 35% faster than 12-core solution (which is natural, given 33% higher core count) and not 50%, as it initially expected. It is also noteworthy that Bulldozer's per-core performance is not projected to be much higher compared to existing microprocessors.
From a performance standpoint, if you compare our 16-core Interlagos to our current 12-core AMD Opteron 6100-series processors (code named “Magny Cours”) we estimate that customers will see up to 50% more performance from 33% more cores. This means we expect the per core performance to go in the right direction - up," explained John Fruehe, the director of product marketing for server/workstation products at AMD.
"We expect to begin shipping our first server platform featuring the Bulldozer this quarter. The Interlagos platform is our first server offering optimized for today's cloud datacenters. The [Bulldozer] [micro]-architecture excels at compute-intensive and HPC workloads, where it will deliver up to 35% performance improvements compared to our current offerings. Customer excitement for Interlagos is high: all of our major customers are expected to introduce servers based on the new platform this year. We are committed to the server market and are focused on returning the business to a growth trajectory," said Thomas Seifert, interim chief executive officer of AMD, during a recent conference call.
http://www.xbitlabs.com/news/cpu/dis...Announced.html