AMD Ontario APU pictured,die size ~77mm^2

[savantu]

The first two sentences is just plain irrelevant, you don't have to tell me those things. And they don't choose 9W because it's closest only, they choose 9W because it's the closest upwards.

So if AMD have a new bobcat based SOC that isn't listed above, with all parts between 10W and 11.5W. What TDP do you think they would give that product?

11.5w

Anyway, your assumption implies the process to be rubbish with power variation of more than 30% between the parts and distribution doesn't follow any pattern. I do not believe that.