By now you've heard that our Half-Life 2 benchmarking time took place at an ATI event called "Shader Day." The point of Shader Day was to educate the press about shaders, their importance and give a little insight into how ATI's R3x0 architecture is optimized for the type of shader performance necessary for DirectX 9 applications. Granted, there's a huge marketing push from ATI, despite efforts to tone down the usual marketing that is present at these sorts of events.

One of the presenters at Shader Day was Gabe Newell of Valve, and it was in Gabe's presentation that the information we published here yesterday. According to Gabe, during the development of Half-Life 2, the development team encountered some very unusual performance numbers. Taken directly from Gabe's slide in the presentation, here's the performance they saw initially:


Taken from Valve Presentation

As you can guess, the folks at Valve were quite shocked. With NVIDIA's fastest offering unable to outperform a Radeon 9600 Pro (the Pro suffix was omitted from Gabe's chart), something was wrong, given that in any other game, the GeForce FX 5900 Ultra would be much closer to the Radeon 9800 Pro in performance.

Working closely with NVIDIA (according to Gabe), Valve ended up developing a special codepath for NVIDIA's NV3x architecture that made some tradeoffs in order to improve performance on NVIDIA's FX cards. The tradeoffs, as explained by Gabe, were mainly in using 16-bit precision instead of 32-bit precision for certain floats and defaulting to Pixel Shader 1.4 (DX8.1) shaders instead of newer Pixel Shader 2.0 (DX9) shaders in certain cases. Valve refers to this new NV3x code path as a "mixed mode" of operation, as it is a mixture of full precision (32-bit) and partial precision (16-bit) floats as well as pixel shader 2.0 and 1.4 shader code. There's clearly a visual tradeoff made here, which we will get to shortly, but the tradeoff was necessary in order to improve performance.

The resulting performance that the Valve team saw was as follows:


Taken from Valve Presentation

We had to recap the issues here for those who haven't been keeping up with the situation as it unfolded over the past 24 hours, but now that you've seen what Valve has shown us, it's time to dig a bit deeper and answer some very important questions (and of course, get to our own benchmarks under Half-Life 2).

Index ATI & Valve - Defining the Relationship
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  • uturnsam - Friday, November 28, 2003 - link

    #110 continued
    Now I know why the guy behind the counter told me to steer clear of the ATI Radeon cards because of the known compatability problems when running games.

    (Computer sales guy thinking-I just read the article in the AnandTech post)

    Translated: I have a shit load of Nvidia cards and if I don't lie my ass off to my Customer's it will be game over for me!!!

    The only reason I started looking at ATI cards was I decided to spend what I saved on the CRT monitor (over the $$LCD) for higher performer card. Mr $Sales$ had me convinced I would be buying an inferior card with ATI. Worth shopping around and scouring reviews :O)
    Reply
  • uturnsam - Friday, November 28, 2003 - link

    I was going to buy a Geforce5600 but looked at a 9600Pro today the thing is I was wondering if I should really blow the budget and lash out on a 9800Pro.
    I am so glad I came across this article I will stick with the 9600Pro, save some cash, sleep better at night and know when half life 2 is released I will be getting the best performance for the outlay.

    Reply
  • Anonymous User - Thursday, October 16, 2003 - link

    you can count on your 9500 being in between the 9800 and the 9600, about 30% frame rate above the 9600. the 4 pipelines will help.
    Reply
  • Anonymous User - Tuesday, September 30, 2003 - link

    I would like to see a test of the dx8 paths on some of the really older cards for those of us who are too broke for these new ones!!

    For instance, I have a geforce2 GTS that I love very much and works just fine on everything else. I don't want to have to upgrade for one game.
    Reply
  • Anonymous User - Sunday, September 21, 2003 - link

    I would like to see how they compare with a 5900 using Detonator 44.03 driver. Yes I know its an older driver. But in my tests it provided higher benchmarcks than the 45.23 driver.

    Has any body else noticed this?
    Reply
  • Anonymous User - Friday, September 19, 2003 - link

    So actually Nvidia shader(16/32) are not
    comparable with ATI shader(24-ms dx9 standard)!
    Too bad in a way or another they try to cheat
    again and again.......
    Very bad idea!
    Reply
  • Anonymous User - Tuesday, September 16, 2003 - link

    #104, the benchmarks and anand's analysis show that hl2 is gpu power limited, not memory/fillrate limited... the 9600 will be limited more by that than by memory or fillrate. Reply
  • Anonymous User - Monday, September 15, 2003 - link

    I think #84 mentioned this, but I didn't see a reply. In the benches, the 9600 pro pulled the exact same (to within .1 fps, which could just be roundoff error) frame rates at 1024 and 1280.

    I don't think I've ever seen a card bump up res without taking a measurable hit (unless it was cpu-limited). In every other game, the 9600 takes a hit going from 1024 to 1280. And the 9700 and 9800 slow down when the resolution goes up, even though they're basically the same architecture. Someone screwed up, either the benchmarks or the graphs.
    Reply
  • Anonymous User - Monday, September 15, 2003 - link

    #61 Did you take the time to see that valve limited their testing use. Anandtech had no say in all the tests because they were very time limited. Also, try to make coherent sentences. Reply
  • Anonymous User - Sunday, September 14, 2003 - link

    It's not as if GIFs gobble bandwidth, I (as CAPTAIN DIALUP) don't even notice them loading. They're tiny. Even though I don't have trouble receiving this Flash stuff, it pisses me off, because sometimes the same scores will load for all the pages. Why not have a poll or something on this? Reply

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