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While particular approaches in graphics processing units design have been pretty different for leading computer visual companies ATI Technologies and NVIDIA Corp., in future the architecture of GPUs from the firms may be fundamentally different, as executives from both companies proclaim different approaches for chip internal architectures.

NVIDIA Disagrees with ATI Technologies

ATI Technologies’ developer relations manager Richard Huddy said last month during a conference in London, UK, that the company’s future visual processing units will feature unified pixel and shader processing. While he declined to elaborate on the timeframes for such chips, he said unified pixel and vertex data processing is a required capability for Windows Graphics Foundation 2.0 that comes our together with Microsoft’s next-generation operating system called Windows Longhorn. On of the benefits the unified approach brings is ability to dynamically allocate chip resources depending on the demand for pixel and vertex processing, Mr. Huddy said. Another one is simplified software development.

NVIDIA Corp.’s chief architect David Kirk called the unified graphics engines as an implementation detail, not a feature, but admitted the unified architecture would be nice for programmers, who would have one instruction set for vertex and pixel shaders.

“It’s not clear to me that an architecture for a good, efficient, and fast vertex shader is the same as the architecture for a good and fast pixel shader. A pixel shader would need far, far more texture math performance and read bandwidth than an optimized vertex shader. So, if you used that pixel shader to do vertex shading, most of the hardware would be idle, most of the time. Which is better – a lean and mean optimized vertex shader and a lean and mean optimized pixel shader or two less-efficient hybrid shaders? There is an old saying: ‘Jack of all trades, master of none’,” Mr. Kirk said in an interview with ExtremeTech web-site.


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