"If I have read it once, I have read it a thousand times, “The Xbox 360 is just ATI’s next generation (fill in favorite code name here) GPU.” The simple answer to that is, “No it is not.” While most modern GPUs share many architectural similarities, Bob Feldstein and Chris Evenden of ATI went out of their way to explain to me, no matter how hard I tried to convince them otherwise, that the Xbox 360 GPU is very much an original creation. While some will try to tell you that is it simply a modified DirectX 9 GPU, you might be interested to learn that the only API spec that the Xbox 360 hardware meets is its own API. That is correct, the Xbox 360 GPU only meets it own Xbox 360 API specifications. While of course some lessons learned in DX9 and upcoming DX10 were applied, the GPU of the Xbox 360 is very much its own and comparing it directly to anything in the PC world is simply “not right” according to Mr. Feldstein. Obviously, the Xbox 360 can be thought of as a very innovative solution specifically for the Xbox and only the Xbox."
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