regarding X360's Xenos calculating over 6B vertices per sec

[Megadrive1988]

what was the exact quote from ATI (posted here on B3D) regarding the
Xbox 360 Xenos GPU ability to theoretically calculate or transform (but not setup) over 6 billion vertices per second, if using ALL of its unified shader ALUs for the geometry side?

I am very well aware of the hard triangle-setup limit of 500 million polygons/triangles per second.


the very high theoretical Xenos geometry figure (disregarding triangle setup limit) was somewhere over 6 billion. out of sheer curiousity, what was the exact figure, and looking at PS2's spec (not PS3) with Emotion Engine and Graphics Synthesizer, what PS2 spec figure is comparable to to the 6+ billion verts calculated by Xenos? the 66 million of Emotion Engine (or as Panajev said a few times, 100+ million using every unit in the EE) ??

 

[Dural]

ATI? I thought it was ERP that said that.

 

[pc999]

Dave B., had said that (somehere in this forum), I am not sure if others had too,ERP said that this would possible but probably with XB level shaders.

 

[Megadrive1988]

Dave B., had said that (somehere in this forum), I am not sure if others had too,ERP said that this would possible but probably with XB level shaders.

I believe the 500 million triangles per second would be possible with Xbox1 level shaders, not the 6 billion verts per second peak calculation rate.

 

[ShootMyMonkey]

I believe it was basically the idea that the simplest vertex program you can have is one that simply transforms the position -- 4 dot products, i.e. 4 instructions.

Assuming perfectly staggered threading,
48 units / 4 instructions = 12 vertices per cycle * 500 MHz = 6 billion.

I'm not sure about an immediately comparable figure for PS2, but there was some obscenely ridiculous claim for Xbox's GPU (might have been at GDC), that was only achievable if you rendered a single tri (no texture, no color, and every pixel deliberately failed alpha test, so it basically took zero fillrate) without ever moving it at all and thereby keeping all the vertices in the post-transform cache. It's probably similar to that.

 

[Megadrive1988]

I believe it was basically the idea that the simplest vertex program you can have is one that simply transforms the position -- 4 dot products, i.e. 4 instructions.

Assuming perfectly staggered threading,
48 units / 4 instructions = 12 vertices per cycle * 500 MHz = 6 billion.

I'm not sure about an immediately comparable figure for PS2, but there was some obscenely ridiculous claim for Xbox's GPU (might have been at GDC), that was only achievable if you rendered a single tri (no texture, no color, and every pixel deliberately failed alpha test, so it basically took zero fillrate) without ever moving it at all and thereby keeping all the vertices in the post-transform cache. It's probably similar to that.

thanks for that post ShootMyMonkey. makes sense to me now. when I thought about making this thread, I was basicly wondering if a comparison could be made between PS2 EE's 66 Million and X360 Xenos' 6 Billion, which are both not-achievable in games. but it seems like Xenos' 6B is less achievable than EE's 66M, and a better comparison might be to Xenos' 1.5B verts (which I believe is derived from the 500M triangle setup limit) .....

what's the Playstation2's triangle setup limit, btw?

 

[version]

"what's the Playstation2's triangle setup limit, btw?"

75mil

 

[pc999]

Dave B., had said that (somehere in this forum), I am not sure if others had too,ERP said that this would possible but probably with XB level shaders.

I believe the 500 million triangles per second would be possible with Xbox1 level shaders, not the 6 billion verts per second peak calculation rate.

Yes, you are correct.
Sorry had only made a quik post, and explained myself wrong.

 

[Megadrive1988]

Dave B., had said that (somehere in this forum), I am not sure if others had too,ERP said that this would possible but probably with XB level shaders.

I believe the 500 million triangles per second would be possible with Xbox1 level shaders, not the 6 billion verts per second peak calculation rate.

Yes, you are correct.
Sorry had only made a quik post, and explained myself wrong.

no problemo' - I do the same all the time