Unraveling The AMD 65nm Riddle

When AMD came out with their first 65nm X2 CPUs, a lot of fans were wondering if AMD was going to be in a good position to ramp up their existing X2 line.  If that happened, AMD might have been able to close some of the performance gap between the Core 2 Duo and the X2.

Sadly, that never happened.  Instead, fans and hardware aficionados ended up scratching their heads, and have been puzzling over the whole situation ever since.

Initially it was rumored that AMD may have been experiencing technical difficulties with the new process, something that is actually quite common in the industry.  A new process often results in a low percentage of viable chips, or yield, until it can be perfected.  It often takes a long time and lots of money to iron out all the kinks in a new manufacturing process.
“But 65nm yields are good, AMD can make faster parts, but it would not make economic sense. There is no 65nm 1MB component, so why crank up 65nm 512K speeds for a quantifiable clock for clock performance loss at potentially no cost savings to AMD?

While upping 65nm speeds are possible, without Barcelona, it doesn't make sense. Barcelona is late, it screwed up AMD's plans, and 65nm was one of the victims.”
While all of these reasons are speculation, they do have the ring of truth to them: AMD didn’t want to use their limited engineering resources on migrating the 1MB/core X2s over to the new process while they were simultaneously trying to get Barcelona off the ground.  Once it became clear that Barcelona was going to be late AMD had a choice.  They could either rethink their earlier choice, or stick by the above logic and increase the clock speed of their 90nm parts as a last ditch maneuver.

Either way, the net result is that Barcelona would have a bit more competition from within AMD’s own lineup.