obobskivich wrote:

This contains nVidia's statement on NV30's internals (and some of TR's interpretation and measurement): http://techreport.com/r […]
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This contains nVidia's statement on NV30's internals (and some of TR's interpretation and measurement):
http://techreport.com/review/4966/nvidia-gefo … 800-ultra-gpu/4

It can do 8 texture/stencil/shader operations per clock, but only 4 color+z operations per clock. Per other nVidia specs, it also supports 16 textures per pass (this includes NV30). "8x.5" may be more accurate then, but overall it gets quite screwy in real-life because it isn't like 3DLabs P10 where it's "locked" in one array mode or another. Instead this all dances back and forth in real time (clock to clock); I don't know to what extent it supports "mixing and matching" across its available resources, which is where "8x.5" may or may not make better sense.

On the stencil/shadow thing, per this (http://www.nvidia.com/object/feature_ultrashadow.html) it appears all of the FX chips support two-sided stencil and should handle stencil shadowing (if I'm reading correctly), but the NV35 added shadow culling, which is meant to improve performance (like HyperZ), but appears to be tied to the renderer, as opposed to the hardware, so the developer would have to implement it ("programmers can define" as opposed to "the blessed chip automatically figures out"). In a Tom's Hardware comparison, 5800 and 5900 performed almost identically in a Doom 3 test, which could potentially be interpreted as a lack of shadow culling support (or importance).

Oh I see where you're coming from with the 16 textures per pass aspect. Yeah that is a Direct3D 9 spec IIRC so all compliant GPUs have that capability. When I say 8x0, I am referring to the 8 texture/stencil/shader operations per clock aspect. It was a Beyond3D thing I think.

You're right - they certainly are curious GPUs.

Interesting about Doom3 and NV35 equaling NV30. Maybe another game using the engine implements that stencil extension. Or perhaps it is unnecessary with NV4x and so just went ignored.

swaaye wrote:

Oh I see where you're coming from with the 16 textures per pass aspect. Yeah that is a Direct3D 9 spec IIRC so all compliant GPUs have that capability. When I say 8x0, I am referring to the 8 texture/stencil/shader operations per clock aspect. It was a Beyond3D thing I think.

Yes 16 tex/pass is a DX9 spec afaik - 9700/9800 also support that too afaik. I looked through the tidbits I've collected on REALiZM over the years, but couldn't find that specifically mentioned one way or another. 😊

Otherwise I think we're on the same page. 😀

Interesting about Doom3 and NV35 equaling NV30. Maybe another game using the engine implements that stencil extension. Or perhaps it is unnecessary with NV4x and so just went ignored.

From the nVidia page, it looks like the "shadow cull" (UltraShadow) was an FX 5700/5900 thing, and GeForce 6/7 got UltraShadow II (http://www.nvidia.com/object/feature_ultrashadow2.html). The documentation for that shows it as a feature in Doom 3, but this may be a mod/developer build/whatever as opposed to the retail game. In both cases Doom 3 seems to be their big push for this feature.

It sounds like Ultrashadow 1 = GL_EXT_depth_bounds_test or DBT (Depth Bounds Test) for D3D. Supported initially by 5700 and 5900, as you say.
http://oss.sgi.com/projects/ogl-sample/regist … bounds_test.txt
http://aras-p.info/texts/D3D9GPUHacks.html

Interestingly the Radeon HD 7xxx series is the first Radeon to support this.
http://www.geeks3d.com/20130523/amd-gcn-perfo … demo-published/

Doom3 source does seem to contain it per web searches...

For a minute there I thought you mean "original Radeon" with "7xxx" but then remembered: they have released "Radeon 7000 series" twice. Once in the early 2000s as a DX7 card, and once again a few years ago as a DX11 card. 🤣 I'm kind of tempted to setup and do some comparisons with NV30 and NV38 in Doom 3 based on this - seeing the 5800/5900 score almost identically in Doom 3 makes me wonder how significant this feature actually is/was... 😊

obobskivich wrote:

For a minute there I thought you mean "original Radeon" with "7xxx" but then remembered: they have released "Radeon 7000 series" twice. Once in the early 2000s as a DX7 card, and once again a few years ago as a DX11 card. 🤣

I've now added "HD" to that sentence. 🤣

obobskivich wrote:

I'm kind of tempted to setup and do some comparisons with NV30 and NV38 in Doom 3 based on this - seeing the 5800/5900 score almost identically in Doom 3 makes me wonder how significant this feature actually is/was... 😊

Yeah it is interesting. For comparison, with idTech4, I think you can just enable/disable the support for the extension.

After amputating all the sick parts my NV Silencer 5 is working again, I put it on my PCI-E Geforce 6800GT.

The idle temp isnt as good as it was with all limbs attached but its no worse than with the stock cooler, the load temp is ~65C at Ultra clocks and the cooler is still silent.