"Think thermals, think on-chip noise, and think circuit marginalities. "
Those things are certainly possible. And they can be nasty. But Penryl could be suffering from the same things. In fact, are probably more likely given that it is on a smaller process. If AMD had a track record of dog and pony shows with lots of eye candy like Intel does, this would be a very telling point. But the fact of the matter is that AMD hasn't done these things in the past. Which leaves things in a more ambiguous state. Sadly, running Task Manager is pretty typical. Their marketing people suck rocks.
AMD is famous for not being particularly transparent. Ever. I remember one poster swearing up and down that the original K8 had not taped out because there wasn't a big tent party. This was about a week before they had a public demo of the chip. Yes, it was a closed box demo running Windows and not much more. Obviously it had taped out something more than a week before...
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