NVIDIA: Beyond G80...

Newegg is out of BFG 8800GTS 640s and GTXs and Ultras. Atleast they had none listed yesterday. Had 2 320MB versions thou.

 

http://www.vr-zone.com/?i=5127

This is make G80s almost a year old. No details on G92 though.

 

It is definitely time for another GPU to discuss.

 

Take a look at some leaked specs posted over at XBit Labs.....
http://www.xbitlabs.com/discussion/3953.html

 

Weird. For years now we've been seeing rumours pop up with specs for the upcoming hot new thing from one of the IHVs which read as if someone has posted a "what would you like to see in teh next-gen??!" thread on a forum, then collated the suggestions and circulated them as fact. These "specs" read just like that.

512-bit external memory bus and eDRAM? What's with that then?

Built-in audio chip... presumably because ATI did something similar?

GPGPU native... what the hell is that?

Sprinkle in some stuff we already know about (double-precision FP) just to add a bit of credibility, and hey presto you've got yourself an Internet rumour.

 

Its posted in the forum from a user not xbitlabs news, and the post date is 2007.06.03

Half of the spec r600/xenos already support/have/done

- Second Generation Unified Shader Architecture. - R600
- Fully Scalar design. - R600
- 512-bit memory interface. - R600
- 1024MB GDDR4 graphics memory. - R600
- eDRAM die for "FREE 4xAA". - Xenos (well its not so free, only in paper)
- built in Audio Chip. - R600
- built in tesselation unit (in the graphics core" - R600

So the whole specs list sounds like a fanboi dream specs

 

And how sounded the G80 spec, when we heard these first time?

 

don't we expect an updated G8x? pretty big changes for a refresh isn't it?
and off course the edram die bears no credibility.

 

Normal

R600 specs get a "wow" factor from many user when they see first time and now when its real almost all of them dissapointed, so specs say nothing about real world performance.

 

Technically speaking G71 is an updated NV30 8)

 

On the PC ? It's the first generation, not second, no matter what the marketing tells you.
Xenos is irrelevant because it's neither fully Direct3D 10-compatible nor a PC component to start with.

Nope. Only the Geforce 8xxx is a Fully Scalar design.
The R6xx is a combination of scalar and vector units.
Both approaches have their advantages and drawbacks, but i think it's currently generally accepted that going fully scalar is the future tendency with either IHV, as complex shading increasingly becomes norm.

And indeed it is, especially since neither GDDR4 nor a 512bit bus were enough to offset the current kings, 8800 GTX/Ultra.
As for the audio processing and the tessellation unit, they became largely ignored, but we'll see if a dedicated unit of the latter is worth it next to DX10's Geometry Shader functionality (which is able to achieve similar results under the right circumstances).
The audio chip ?
With certain Zotac 8400 GS and 8500 GT cards able to do practically the same thing using nothing more than a motherboard built-in audio coded, a pass-through cable and a DVI-HDMI adapter with audio support, just like R6xx, i see no point in further complicating driver development and testing with such trivial features, especially in the gaming world where a high quality onboard codec or an add-on sound card is a must.


In my opinion, we'll see no more than 192~256 scalar units on a high end 65nm G9x, a 2.5 ~ 3GHz shader core and a bus no larger than 448bit (if not unchanged from the current 384bit one), in addition to FP64 and DX10.1. OpenGL 3.0 might not be so "in the bag", though.

 

Thats no difference. Its still a design that we were able to evolve from.

Nope. Superscalar is the correct term.

Driver development is hardly complicated as the drivers are already available elsewhere or even directly supported by Windows (Vista) in our case. As for the cable solution, the you also run the risk of decreasing your output options by loosing the digital output from the back of the PC and only having the HDMI option.

 

Given the much greater degree of design liberty in a closed spec console environment, i still don't see it as such, sorry. You should know more than me of course, but on the outside the R600 looks more like a hybrid of R5xx and Xenos technologies designed towards Vista's new requirements.
That doesn't necessarily make it a bad thing, however.

You came in late, as i had edited out the "Superscalar" term of my original post in the hopes of not confusing my direct interlocutor any further.

Anyone using more than one digital audio output should be using a receiver anyway, and there are plenty of them with multiple HDMI In/Out ports.
Also, there are still the prevailing analog connections and source mixing at your disposal after the digital out is used up, especially with Vista's software-based audio driver architecture.

 

Those specs are more suspicious than a 3 dollars note.

 

I don't see how you could see R600's shaders as anything but an evolution of Xenos. R5xx has fixed vector based ALU's, Xenos had unified vector ALU's and R600 has unified scalar ALU's. Thats a technological progression at each stage in my book (thats not to say Xenos actually has more outright shader capability than R5xx).

 

nV did audio on the GFX card about 10 years ago already. Died a painful death back then, but who knows if it would work out in a new, better design.

About eDRAM, that sounds rather enthusiastic (or more precisely, like a pipe dream).

 

Err, no. It's not a scalar design. It's also ATI's first unified design for the PC and not all that similar to Xenos at all.

I wouldn't call that an audio chip. Or can it be used for regular audio with Windows? Can you connect your boxes to it and get rid of the sound card? No.

 

Well, to me, a 512-bit bus doesn't seem all that likely either. The 384-bit bus should do them well enough for the time being, unless they find that the weird memory amounts required by the 384-bit bus make the part less marketable. A dedicated tessellator also seems a bit unlikely. Though we might potentially expect improved geometry shader performance, I rather doubt they'll do what ATI did here.

I also believe it was confirmed that 64-bit floating point will not make it into the next high-end consumer-level part. So yeah, all-in-all, the rumor seems to be mostly a pipe dream.

 

They (ATI) are calling it the second generation. But does it really matter? Especially when their second generation can't keep up with the NV's first?

Why not? You gonna need an HDMI decoder though.

 

Because it lacks most of the functionality of a "regular" sound card? Wouldn't do, unless you do it all in SW and let the shaders do the processing or some such, which would be just a half-arsed SW-hack.