Nvidia GT300 yields are under 2%

[eRacer]

Because the article I had seen said it would be larger than the 55nm GT200b, but smaller than the 65nm GT200.

Assuming there are 104 dies on a wafer as Charlie said, then according to my die size calculator the die area will be about 534 mm^2 if the die happened to be almost perfectly square (~23.1mm x ~23.1mm). That would fit what you read in the article with the size being between GT200 and GT200b.