ATI confirms next-gen GPU to be Unified Shaders

[cadaveca]

I was talking to a fellow member here yesterday on just what was going to come out from ATI next...only to have it later confirmed by Rick Bergman, by way of an analyst's meeting. Now, everyone should be aware that Vista is just around the corner, and it's merely legal litigation that keeps M$ from putting product on retail shelves.

Anyway, last night, Beyond3d published this little tidbit:

At a recent analyst session ATI’s Senior VP of PC Business, Rick Bergman, has confirmed that their next generation of PC graphics products will feature much of the technology developed for "Xenos", ATI’s XBOX 360 graphics chip. We’ve surmised that this is likely be the case previously, given that Xenos utilises a unified shader architecture at the hardware level, with both Pixel Shaders and Vertex shaders utilising the same ALU resources it becomes a ripe time to implement it with DirectX10 unifying the vertex and pixel shader programming capabilities in the API.

Vertex and pixel processing have previously always been separate hardware functions, though vertex processing moved from a software based solution to hardware with the introduction of NVIDIA’s GeForce 256 and has subsequently got closer to the pixel processing capability with each revision of DirectX Shader Model, to the point where DirextX10 will should dictate the same programming capabilities across both. Even with this being the case there is nothing to suggest that the hardware has to be unified for processing as pixel operations generally have to hide greater latencies than vertex operations thanks to the greater use of texturing in the pipeline. However, Xenos’s design has attempted to remove the texture latency issues from shader programmes by creating a highly threaded design that separates texture instructions from ALU instructions, allowing multiple shader batches to run concurrently, and so it comes as no surprise that ATI should adopt this architecture for the PC, seeing as the investment has already been made.

So, it seems my sources were correct in this matter, but there was also words of what the competition planned...a GPU that DID NOT feature unfied shading.

Digging a little deeper revealed that the sources used for this info are quite old, and coming from nVidia themselves officially, the comment could be taken either way...but was blatantly an attack @ M$ and thier seeming favortism with ATI and DirectX API's(due most likely to the working relationship between ATI and M$ on the XBOX360), citing that M$ made API's and not hardware, so (M$) didn't know what was needed in the first place in the current market.

However, the timing of that market was over 6 months ago, when M$ was knee-deep in copy-right lawsuits, with no clear picture as to the end of such. Here and now, most of those cases are settled, and regardless of current issues with various governments and WinXP, most of the issues are readily solved with the myriad of Vista versions.

So, take any info on nVidia with a grain of salt.

[Aedan]

How much difference unified shaders will make is yet to be seen. It is going to be a 'watch this space' to see what actually happens when the apps are released.

[Gizmo]

My own suspicion is that ATI's implementation will turn out to not perform as well as nVidia's, but will be easier to program because the developer won't have to be as concerned about resource allocation; i.e. it will be easier to throw more hardware at a given performance problem.

However, that is just a guess, as I have next to no knowledge of the actual intricacies of DirectX graphics programming.

[cadaveca]

Originally Posted by Áedán

How much difference unified shaders will make is yet to be seen. It is going to be a 'watch this space' to see what actually happens when the apps are released.

You've hit the mail on the head, but when the Xenos gpu in the 360 features the same programming features, and you take into account the sudden drought in "bigname" titles to be released...as well as the delay of a few...we already know that these apps are works in progress, and a few are ready and waiting too.

But like you say, any standard must be adopted first. ATI has the high ground becasue of the xbox360 deal alone...enough that the "ports" over to pc from the 360 can be easily done(in a DX10 environment)...and the support given to programmers from the hardware/software makers(ATI and M$) will already have a built-up foundation which to continue on, while in the meantime, nVidia must scramble to get everything in place, as well as working on the PS3 deal, and thier requirements there, which, although are not quite as intensive as ATI's own console foray, have thier own intricacies that must be smoothed out.


ATI has had unified shading up and running since before the advent of DX9, as this was one of the possible avenues that M$ could have taken at the time. ATI was the sole hardware provider for M$ during the alpha and early beta stages, and this one step ahead for ATI has left a bitter taste in nvidia's mouth, and due to the 360 deal, it only gets worse. this alone has me confident in ATI's GPU...and the fact that they have had several years to work on it, nevermind I say myself the job posting for the driver programmer for the r600. So, regardless of how well the hardware performs, as Gizmo surmises, the app support, as Aedan says, is key...as it's easy to write an app that behaves poorly on one card, and fantastic on another...especially when architectural differences are so great.

[dsio]

The dig that Nvidia had about Microsoft pushing for unified shaders was about June 2005 from memory. They surely would have been constantly re-assessing the situation in that matter since then. But yea, as far as everyone knows, the G80 will be a NON unified shader card, with SM4.0 and DirectX 10 full compliancy.

The upside of that would be that they can still compete, while their competition takes a risk on the unified shader architecture, and see where the dust settles.

My next card is going to be the next to top end G80, unless it flops. I think I might wait a few months myself to see how the dust settles though. Though ATI has declared its position, much of the Nvidia information is still too shakey for my liking.

Crysis from Ubisoft is going to be something to REALLY look forward to, regardless of what card you're running

[madcatmk3]

I have to see which is better, I might swich over to ATI but I doubt it. I'm going ot have to replace my 7800 when DX10 comes out. I just hope the G80 is only around $500.

[dsio]

Originally Posted by madcatmk3

I have to see which is better, I might swich over to ATI but I doubt it. I'm going ot have to replace my 7800 when DX0 comes out. I just hope the G80 is only around $500.

Amen.

[madcatmk3]

Watch it now be $1200

[cadaveca]

depends on the ram used. that's the only reason the 7800 series started @ such high cost. ATI is poised to make the move to DDR4 tho, and are currently working out the kinks in the memory controller. This may make ATI's cards the next $1000+ card, but with hynix's annoucement a while back that i posted here, GDDR4 may not be as expensive as current bins of GDDR3.

[tiamat63]

What are they going to be using? 1.26ns? 1.2ns? or something <1.2ns?