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maha_x
08-24-01, 02:47 AM
I saw this at the MadOnion forums. Somebody had found out that the NATURE demo of 3DM2k1 runs faster when run with software T&L. Tbird 1Ghz and better CPU seemed to do the trick. Up to 10fps speed increase.

Unfortunately the other tests suffer when on software T&L, so U cant benefit from this in yer score.

Best candidate for the reason was that the GF3 GPU was loaded with tasks (T&L, vertex shading, pixel shading), and the mem bandwidth got used up. As there was no difference if the CPU was 800Mhz or 1500Mhz when the HW T&L was enabled. Lowering the resolution helped the HW score, obviously because of the relief on the mem bandwidth. More bandwidth for geometry data.

This, offcourse, stirred alot of talks about Kyro2 and Kyro3. Kyro2 being non-T&L card. Someone speculated even that mayby Kyro3 would come out with only Vertex and pixel shaders, but not with T&L.
To me this makes little sence, because AFAIK the Vertex shading is done before T&L. This would result in sending the vertex shaded data back to CPU for T&L and once more back to the Kyro. Not a viable sollution.
Still, the GF3 performed better with software T&L. So did the vertex shading go to software too? I dont know if these chips use the DX7 hardwired T&L with the vertex shader, or is the whole T&L moved to the shader? If this is the case, the CPU was able to very well cope with the polys while the GF3 was only doing the 2D part of rendering. This again would defy the whole meaning of the T&L unit.

Lets see if U can replicate these results.

RedDeathDrinker
08-24-01, 04:58 AM
The nature test in 3DMark2001 is to test the T&L engine specifically, so without it on, it's way slower. The reason for the drop in the other tests is that with T&L on, the card is running the T&L engine as well. Which sloo oo o w 's i t d o w n......

I think the main aim is to get the best average FPS through the whole test, not just concentrating on one feature.....

You still didn't answer my question about skiing tho'......lol

maha_x
08-24-01, 06:23 AM
Originally posted by reddeathdrinker
The nature test in 3DMark2001 is to test the T&L engine specifically, so without it on, it's way slower. The reason for the drop in the other tests is that with T&L on, the card is running the T&L engine as well. Which sloo oo o w 's i t d o w n......

I think the main aim is to get the best average FPS through the whole test, not just concentrating on one feature.....

You still didn't answer my question about skiing tho'......lol

But as I said, the nature test runs FASTER when the hardware T&L is off.

Skiing??? Have I missed something? Something funny?

RedDeathDrinker
08-24-01, 08:25 AM
Hey Maha_x - it was in response to the statement that

"Somebody had found out that the NATURE demo of 3DM2k1 runs faster when run with software T&L. "

That was explaining why!

BTW - response in another thread to the skiing, where you mentioned you'd like to drive round Scotland, remember? The one where I posted the "Revocation of the Declaration of Independance...". It was called "We've had enough...."

:D