Interesting thread over at [H] about HL2 & nVidia cards
Half Life 2 Coded Against NVIDIA?
This thread in our forum alleges that HL2 is coded to not allow some of NVIDIA's hardware to perform as well as it could. Now as forum threads go, we see a lot of things alleged, but if you are using a last-gen NVIDIA GPU video card, you might give this "fix" a try and see what happens. We have requests into ATI and NVIDIA for their thoughts on this. Valve only sends us form letters now days...
"Again, using 3dAnalyze you can test this. It is capable of forcing a card to use only FP16 shaders no matter what is requested. You'll see no image quality difference doing that - just a HUGE performance boost. Why? Well, because while FP16 is all that Half-Life 2 *needs*, if they let the GeForce FX cards do THAT, they might have been competitive! So, instead, they forced FP24 (unneeded), which caused the GF-FX cards to render the DX9 mode in FP32 all the time. With the obvious associated performance hit."
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