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Old November 29th 04, 09:08 PM
deimos
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DaveL wrote:
Half-Life 2 is ATI's game. Nvidia has Doom3 and that's where the FX cards
shine. We have known it would be this way for more than a year now. So you
just now getting it?

DaveL


wrote in message
...

http://www.petitiononline.com/nvidiafx/




It's not quite that simple. About a year ago or whenever the hell it
was, Valve had a "Shader Day". During this each company tried to demo
their best in the current build of the Source engine. At that time,
Valve had a mixed mode driver in place for FX class hardware. This used
partial precision hints where needed and a modified PS2.0A path to
greatly optimize the default FX performance without any image quality loss.

Editors at the time commented that it ran just as fast in DX9 as an
equal ATI card. This specifically concerned a 5900/U I believe. But
for final release (even after the source code and E3 leaks!), Valve
implemented a single PS2.0 DX9 path requiring full precision for
everything.

Ba-dump... FX performance goes down the ****ter and only driver
optmization or application detection to reorder the instruction in the
dynamic recompiler can help pull it out.

This is in addition to the problems the FX has anyway with instruction
order, pipeline stalls, a multitexture oriented architecture (pixel
shaders are single texture), and being heavily based upon a different
high level shader API, cG.