ATI Radeon HD 4000 Series discussion

[003]

Then why are we not counting R300 as a base for R600?
You simply don't do that...
He said 10 months from G92 to Rv770, which is not the case.

Because the R300 is a totally different (classic, in a sense) architecture. The R600 was pretty much built from the ground up, and each successor to it thus far has been based on its same architecture.

If you want to be really anal, the R600 is technically the successor to the R500 GPU which is inside the Xbox 360, which WAS built from the ground up to be the first unified shader architecture.