PRESS REPS at AMD have returned with an answer to a question we posed last week.
That was in response to a roadmap we pixellated last week about future Barton core speeds, and which you can find here.

We wanted to know why the "Barton 3000+" microprocessor was originally slated to launch at 2.25GHz, but was instead released at 2.17GHz.

Said AMD: "One of the advantages of model numbers is that when cores change you don't have the age-old discussions about guessing how much faster the core improvements make the new products. For instance: 'Is a P4 20% or 30% slower that a PIII, clock for clock?'"

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