Xenos Questions

[DeanoC]

This can't be right as XNA is intended for cross-platform development. MS even suggested Sony use it in PS3. Whatever API is used for XB360, it'll find it's way to PC if it isn't there already, save a few custom OS pieces I imagine.

Regards unified shaders, this is hardware covered by patents, surely? The DirectX/XNA API calls for vertex and pixel shaders, and the hardware either has these as seperate units or unified, but their implementation shouldn't matter to the API.

XNA does not mean the same API on X360 and PC, its simply means a similar set of tools and APIs. X360 DX is highly customised, also MS/ATI are providing hardware specs, so if nessecary you can bypass almost the whole thing and hit the metal directly.

 

[DeanoC]

Seems like incorrectly mixing terms to me. It's simply not the task of an ALU to write out samples to memory.

You really need to wait for Dave's article, R500 is special

R500 can write to EDRAM or GDDR (actually both at the same time...)

The GDDR writes are directly controlled by the ALUs (memexport), its unrelated to the ROPs output though...

 

[Acert93]

DeanoC, you and Dave keep taunting us! You seem to have a pretty good grasp on the design (and all the consoles for that matter). You make me wish you were working on both consoles! After seeing NT's work on Heavenly Sword I am pretty sure you guys will be at the cutting edge of any platform you work on. Keep up the good work... and keep the teasers coming (Both game and hardware related!)

 

[nAo]

R500 can write to EDRAM or GDDR (actually both at the same time...)

The GDDR writes are directly controlled by the ALUs (memexport), its unrelated to the ROPs output though...

I understand this is something different from having multiple render target in n various memory pools, are you implying an ALU can arbitrarily output something anywhere in system memory?
If this is true..well..it would open a new whole world to GPGPU-like processing
(and a brand new world of bugs too )
It would be nice to know if it can even manage mem coherency, but I bet this is left as an exercise to shaders writers

 

[PC-Engine]

DeanoC, you and Dave keep taunting us! You seem to have a pretty good grasp on the design (and all the consoles for that matter). You make me wish you were working on both consoles! After seeing NT's work on Heavenly Sword I am pretty sure you guys will be at the cutting edge of any platform you work on. Keep up the good work... and keep the teasers coming (Both game and hardware related!)

I agree DeanoC and ERP seems like one of the very few unbiased developers around. Even after his game was picked up by SONY, his integrity doesn't seem to have been compromised at all.

 

[Dave Baumann]

If this is true..well..it would open a new whole world to GPGPU-like processing

 

[London Geezer]

DeanoC, you and Dave keep taunting us! You seem to have a pretty good grasp on the design (and all the consoles for that matter). You make me wish you were working on both consoles! After seeing NT's work on Heavenly Sword I am pretty sure you guys will be at the cutting edge of any platform you work on. Keep up the good work... and keep the teasers coming (Both game and hardware related!)

I agree DeanoC and ERP seems like one of the very few unbiased developers around. Even after his game was picked up by SONY, his integrity doesn't seem to have been compromised at all.

There are biased developers? Around here?

 

[Martin Eddy]

If this is true..well..it would open a new whole world to GPGPU-like processing

Damn you dave! When's this article going to be ready?

 

[nelg]

If this is true..well..it would open a new whole world to GPGPU-like processing

Novadex?

 

[AlNom]

Memories of Deano's previous teasing about other uses for the GPU are resurfacing.


aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaah


Dave, go back to writing! *cracks out the whip*

 

[nelg]

The end of "pipelines" as we know them. No wonder the R400 got delayed, this thing is a really ambitious design.

IIRC, a lot of the speculation was that its complexity made it to hard to fabricate. Now it seems it was the lack of an API that was responsible. As far as having a bright future what I find most interesting is its potential for scaling and its low power consumption.

 

[twotonfld]

If this is true..well..it would open a new whole world to GPGPU-like processing

Tease of the day...

 

[Xmas]

You really need to wait for Dave's article, R500 is special

R500 can write to EDRAM or GDDR (actually both at the same time...)

The GDDR writes are directly controlled by the ALUs (memexport), its unrelated to the ROPs output though...

Yes, R500 is special and you already said it has something like 16 memory access units, but in this case ("each of the 16 ALUs has the ability to write out two samples to the 10MB of EDRAM.") it's still incorrectly mixing terms.

 

[Acert93]

Novadex?

Question: Why? Would this not take resources away from the graphics? I could understand this if there was a ton of GPU power sitting idle (e.g. if you had 2 chips in a box), but it seems Xenos is going to be hard pressed to match the PS3 output, putting a physics simulation load would make the issue harder not easier, right?

 

[ralexand]

Novadex?

it seems Xenos is going to be hard pressed to match the PS3 output

? What type of output, image quality wise?

GPGPU-like processing

Can someone explain this term to me? What does the first GP stand for?

 

[Carl B]

GPGPU-like processing

Can someone explain this term to me? What does the first GP stand for?

It refers to using the power of modern GPU's for reasons other than strictly graphics work. 'GP' simply stands for 'general purpose.'

It would be pretty unexpected and fairly wild if the R500 did have any GPGPU applications it could perform - it's something I'm going to wait and read the write-up before I put any hope in.

 

[ralexand]

GPGPU-like processing

Can someone explain this term to me? What does the first GP stand for?

It refers to using the power of modern GPU's for reasons other than strictly graphics work. 'GP' simply stands for 'general purpose.'

Got it, thanks.

 

[Qroach]

And what does "GPGPU-like processing" mean exactly? I'm still trying to figure out what it stands for

 

[nelg]

Novadex?

Question: Why? Would this not take resources away from the graphics? I could understand this if there was a ton of GPU power sitting idle (e.g. if you had 2 chips in a box), but it seems Xenos is going to be hard pressed to match the PS3 output, putting a physics simulation load would make the issue harder not easier, right?

Until we know how efficient the R500 is I would think that it would be premature to say that it will be hard pressed to keep up with the PS3. The way I see it (just guessing) is that the majority of the Xbox's programable FLOPS reside in the GPU whereas they mostly reside in the CPU for the PS3. Considering one of the main benefits of the physics API is its scalability, giving programers access to those FLOPS to use however they may see fit is a possibility., regardless of where they lie.

 

[MechanizedDeath]

Until we know how efficient the R500 is I would think that it would be premature to say that it will be hard pressed to keep up with the PS3. The way I see it (just guessing) is that the majority of the Xbox's programable FLOPS reside in the GPU whereas they mostly reside in the CPU for the PS3. Considering one of the main benefits of the physics API is its scalability, giving programers access to those FLOPS to use however they may see fit is a possibility., regardless of where they lie.

Wait...let me get this straight. Are we now considering the possibility of Xenos to do physics calculation with some free FLOPS? :? Would this be for physics-based graphics? Also, is this general-purpose stuff anyway related to the PPP that's supposed to be on Xenos? This is a wrinkle and a half. :? PEACE.