I think safest bet would be modified faster clocked 7800GTX...but Nvidia could have implemented some features from not yet released G80 and that could be the reason that Nvidia is holding up information about RSX. In terms of number of pipelines...I don't think it would be different from 7800GTX...which is 24+8.
RSX pipeline speculation?
- Thread starter j^aws
- Start date
Perhaps we are wrong assuming that the RSX is a derivative of an existing Nvidia architecture.
The facts that we know are:
-No Embedded DRAM.
-No Unified Shader.
-51M Dot/Products combined with the Cell.
-136M Shader Instructions.
The first possibility and the most repeated inside the internet forums is the idea of RSX=overclocked GeForce 7800 (and I have to admit that I was with this idea in mind until I readed the post of Jaws that have started this discussion).
After reading the post from Jaws I have used the brain a few I have now the idea that in the Cell all the work is multitask and every one of the elements is doing a task simultaneos, being the PPE the element that moves the main code of the game and the SPE thinks like the OS, Physics of the game, Sound and Colission detection. This marks 4 SPE fully operational on this tasks and 3 Free SPE for be the assistants of the RSX.
The 3 Free SPE has a power of 9M Dot-Products, with this we have a number of 42M Dot-Products and we know that every one of the Vector ALU on the Shaders can do 0,55M Dot Products..
Pixel Shader has 2 Vector ALU.
Vertex Shader has 1 Vector ALU.
My idea is that the number of Vertex Shader was reduced from 8 to 4, the reason is that the Xenos can "only" make 500 milion vectors and in the next gen the idea of the micropolygon is important. With this reduction we have aprox 40M Dot Products for the Pixel Shader that is translated to 20 Pixel Shaders.
In other words the config could be:
4 Vertex Shaders.
20 Pixel Shaders.
The problem with this scenario is the transistor count but since the demo in real time of MGS4 and since I win my salary editing videos I can see how the demo uses some effects from the video and photo edition and not from the 3D edition. I believe that the element under the NDA is a module that can apply effects like Motion Blur, HDR and other effects in real time making the work more easy for the rest of the RSX, this module cannot be combined with the Cell because isn´t programable.
The facts that we know are:
-No Embedded DRAM.
-No Unified Shader.
-51M Dot/Products combined with the Cell.
-136M Shader Instructions.
The first possibility and the most repeated inside the internet forums is the idea of RSX=overclocked GeForce 7800 (and I have to admit that I was with this idea in mind until I readed the post of Jaws that have started this discussion).
After reading the post from Jaws I have used the brain a few I have now the idea that in the Cell all the work is multitask and every one of the elements is doing a task simultaneos, being the PPE the element that moves the main code of the game and the SPE thinks like the OS, Physics of the game, Sound and Colission detection. This marks 4 SPE fully operational on this tasks and 3 Free SPE for be the assistants of the RSX.
The 3 Free SPE has a power of 9M Dot-Products, with this we have a number of 42M Dot-Products and we know that every one of the Vector ALU on the Shaders can do 0,55M Dot Products..
Pixel Shader has 2 Vector ALU.
Vertex Shader has 1 Vector ALU.
My idea is that the number of Vertex Shader was reduced from 8 to 4, the reason is that the Xenos can "only" make 500 milion vectors and in the next gen the idea of the micropolygon is important. With this reduction we have aprox 40M Dot Products for the Pixel Shader that is translated to 20 Pixel Shaders.
In other words the config could be:
4 Vertex Shaders.
20 Pixel Shaders.
The problem with this scenario is the transistor count but since the demo in real time of MGS4 and since I win my salary editing videos I can see how the demo uses some effects from the video and photo edition and not from the 3D edition. I believe that the element under the NDA is a module that can apply effects like Motion Blur, HDR and other effects in real time making the work more easy for the rest of the RSX, this module cannot be combined with the Cell because isn´t programable.
Well, we only assumed that RSX is a derivative of the 7800 because NVIDIA said so.
Personally, i can't make out why it's taking so bloody long to get the chip done if it's based on an already existing and released chip. Sure they had to add the FlexIO interface and all the rest, but it seems to be taking an awful long time.
Maybe they're changing more than we know. Lots of people have been saying that an architecture like Xenos would have fit in with Cell a lot more than a "faster 7800". Maybe they're acting accordingly.
But as it stands, from NVIDIA's lips we only got that RSX is a "faster 7800", so i guess we should go for that one. Unless i'm missing something.
Personally, i can't make out why it's taking so bloody long to get the chip done if it's based on an already existing and released chip. Sure they had to add the FlexIO interface and all the rest, but it seems to be taking an awful long time.
Maybe they're changing more than we know. Lots of people have been saying that an architecture like Xenos would have fit in with Cell a lot more than a "faster 7800". Maybe they're acting accordingly.
But as it stands, from NVIDIA's lips we only got that RSX is a "faster 7800", so i guess we should go for that one. Unless i'm missing something.
Don't you guys find it weird?If the RSX is just a souped up G70 with some extras Nvidia will have already gone all out to tell everyone how proud they are that their 7 series GPU made it into the PS3.Why are they still so quiet?
Even the latest Stringer comments didn't even touch a single bit about the RSX.All Sony talked about all this while was how powerful their Cell cpu is and nothing more.Besides the CPU the GPU is one of the key component of a sucessful game console today.Nothing further has been mentioned about it till now.I bet there is something sure up their sleeves which they aint prepared to tell.Be p[repared for some surprise very soon.
Even the latest Stringer comments didn't even touch a single bit about the RSX.All Sony talked about all this while was how powerful their Cell cpu is and nothing more.Besides the CPU the GPU is one of the key component of a sucessful game console today.Nothing further has been mentioned about it till now.I bet there is something sure up their sleeves which they aint prepared to tell.Be p[repared for some surprise very soon.
I'm inclined to think RSX is more than just a souped up G70, as that'd just be sooo boring! Plus they've had lots of time on this device, more then needed I think to get in FlexIO and a 90nm process. We know RSX is cache coherant with Cell and I'm sure there's more going on somewhere. Hope so 
Shifty Geezer said:I'm inclined to think RSX is more than just a souped up G70, as that'd just be sooo boring! Plus they've had lots of time on this device, more then needed I think to get in FlexIO and a 90nm process. We know RSX is cache coherant with Cell and I'm sure there's more going on somewhere. Hope so
I would be extremely surprised if it was anything more than just some tweaking for the specialized purpose, much like the NV2A was in the Xbox.
Why should Nvidia put in any more effort than they have to? They won't make any more money if they do, so what's the incentive to put in more work and expense into RSX development than is absolutely necessary?
_phil_ said:
Agreed. It gave the NV2A the vertex power of a Geforce4, that's why some people called it a "modified GF4".
Because Sony have contracted them to make a GPU part and are paying them to do this. They'll put in whatever Sony asks, and if Sony want a trichromatic-inverse-tachyon-pulse rendering engine, nVidia will put one in.Powderkeg said:
Shifty Geezer said:
You mean it's not there already?
Um, no. I'm under NDA so deny everything.