truform performance on the ati Xx00 series

[see colon]

it's getting time for me to upgrade, and i'm curious about the truform performance of the newest ati cards. i currently have a 9700 and i am pretty displeased with the truform support considering how solid it was on the 8500. thus far, none of the reviews i've read ran any sort of truform benchmarks, some haven't even mentioned truform anywhere in the review. i would assume that the performace penalty would be similar to what i'm seeing with my 9700, but the general consensus is that the Xx00 series is a vertex monster compared to other cards. i don't see truform as a make or break feature, but i do like using it in the games that support it.

so, if anyone could direct me to a review or, possibly, if they own a Xx00 series card possibly run a few tests and post their results that would be great. the dolphin demo from ati's developer site would be an easy test.

http://www2.ati.com/misc/demos/ATI-8500-Dolphin-Demo-v1.1.exe

 

[bloodbob]

I'm fairly certain its not hardware accelerated.

 

[SsP45]

I've run the Dolphin demo on my X800 XL, any way of seeing fps for both sections of the screen?
________
GSX600F

 

[Gnerma]

I tried running that demo, but it told me I needed a card that supports npatches (X800XL, Cat 5.4)

Why is this an issue? Isn't any game that supports Truform going to perform very well on an X800 hardware regardless of what you crank up? I don't think any of them are particularly new or demanding.

 

[IgnorancePersonified]

Yeh - was always disapointed with that one. CS had some big diferences with the models heads.

 

[Ostsol]

I tried running that demo, but it told me I needed a card that supports npatches (X800XL, Cat 5.4)

Did you turn on the option in the CCC or control panel?

Why is this an issue? Isn't any game that supports Truform going to perform very well on an X800 hardware regardless of what you crank up? I don't think any of them are particularly new or demanding.

If it's not fully hardware accelerated, as it was in the R200, then it should be CPU and/or bus limited. With PCI-Express the latter should not be the case, but the reliance on CPU power will certainly be heavier.

 

[Ladis]

I think, TrueForm is fully hardware accelerated on Radeon 8500-9250 only. The next cards don't support it directly (R 9500+), but i think it's "emulated" via Vertex Shader (still computed in hardware ). I think it's a deprecated technology (not widely used and not integrated in Direct3D) so ATI drivers' default setting is "disable trueform" (you have to select "application preference" in the control panel to enable it).

I tried TrueForm yesterday Unreal Tournament was fast on brother's AIW Radeon 8500 but it was quite slow on my Mobility Radeon 9600 :?

 

[akira888]

Ladis:
The R200 cards (8500, 8700, 8800, 9100) have hardware acceleration for PN-Triangles/N-Patches while the RV250 and RV280 cards (9000,9200,9250), like the R3XX and R4XX series, do not have it.

HW Truform, four TMUs, and one vertex shader unit were removed from R200 -> RV250.

 

[see colon]

I think, TrueForm is fully hardware accelerated on Radeon 8500-9250 only. The next cards don't support it directly (R 9500+), but i think it's "emulated" via Vertex Shader (still computed in hardware )

this was my understanding, but i really haven't looked into it at all. if it was purely a software solution, like it was for the 7000 series (for one driver release to hype up the 8500's launch) i would expect a huge performance hit. anyway, i was wondering if the extra vertex power the Xx00 series had made a difference.

I've run the Dolphin demo on my X800 XL, any way of seeing fps for both sections of the screen?

not for eaxh section of the screen, but you can control tessellation on the fly. in my experience the framerate is pretty stable (ie without fluxuation) at any given tessellation level, although it takes a nosedive once the model starts getting "round".

 

[Ladis]

Ok For applicants, it's the GL_ATI_pn_triangles OpenGL extension.

 

[Pete]

According to FRAPS, the dolphin demo's pegged to 85Hz monitor refresh with a 9800P, XP 2400+. Don't know if this helps if it's all being done on the CPU, though. CPU usage seemed to be 100% no matter the tesselation.

 

[see colon]

interesting...
i remember getting a decent performance hit even on my Axp2600+r9700, and i just ran it now (A64+9700) and it seams smooth. i loaded up fraps and re-launched the demo and got a "you card doesn't support truform" error. disabled and re-enabled truform in the CCC, same thing. quit fraps and relaunched, same thing. wierd.