The New and Improved "G80 Rumours Thread" *DailyTech specs at #802*

That's really weird. What's the point in having a unified architecture if you then throw away one of the big things it gives you, ie being able to dynamically assign whatever resources you need at the time from your pool of transistors? Seems totally bizarre to have a unified archtecture acting as if it's a fixed architecture, so I'm inclined to belive that either someone has the wrong info, or G80 isn't really unified (except possibly in the "we are coining a marketing buzzword to confuse people" sort of way).

 

Here's what was mentioned. I tried to translate it as best as I could:

"DX10 performance can of course not be tested. About the physics part, there is no seperate dedicated physics chip. The unified shaders will take care of that (that's why it's got so many onboard - 128. DX10 performance can not be derived from DX9 performance, because the drivers make the unified shaders work as dedicated pixelshaders and vertexshaders. So in a real DX10 game the GPU will behave differently."

Oh some other tidbits I've been hearing, but I'm not 100% sure about it's credibility, but I guess I can write it here. Just take it with a grain of salt.

Availability of G80 will be bad... or at least it will look bad, probably because of high demand. One source said that availability will be bad and that the lifespan of G80 will be short. NV has G81 waiting in it's wings to fix the availability problem. Nothing was mentioned about the G81 architecture, but G81 could be to G80 what G71 is to G70. Scheduled release: Spring 2007.

Oh and R600 was also mentioned... It will most probably be released in the last week of January 2007 (does this coincide with the Vista release?). The exact date given for launchdate was a Saterday so that's a bit weird...

 

Or 65nm G81?

Jawed

 

None except maybe SS2 support HDR so unfortunatly that ain't very helpful :/.

 

it's disappointing, all games he tested worked at 100FPS or higher, so that's only 25% improvement

 

Good, one 7900 TX, does 15 fps in many games to 1280x1024 - COJ, Oblivion, FEAR Extraction point… 15 +20 = 35 fps

 

TheInq is reporting poor availability, though not because of demand, but because retailers arn't getting many (200 units for the whole of the UK on launch day). As ususal, us Brits are being totally screwed on the price. Poor yields? Or maybe profit margins are so poor on such a large, multi-chip card, G80 will get the headlines and kudos for being the first DX10 card, then will be end-of-lifed very quickly in favour of the more profitable G81.

 

In my experience, no flagship GPU has ever had low profit margins upon release. Quite the contrary.

And the cost of a mature TSMC 90nm process technology GPU design is probably lower than a TSMC top-of-the-line 80nm process, with all options.
That's why RV570/560 and G73-B1 are released first, to test the process on less complex designs and with most process performance options still unused.
Get the basics right first, performance comes next.

Nvidia had done the same with 90nm, testing it first on the C51 (Geforce 6100/6150) IGP's in November 2005, before the G71/G72/G73 came out in the Spring 2006.

 

I`ve heard from someone who is testing GF8800GTX that it`s performance in Oblivion is excellent.... He reported that in 1600x1200 AAx8/HDR min fps outdoors on GF8800GTX is higher than average fps on GF7900GTX in 1280x1024 without AA....

 

I get the idea that Gibbo is very pro-Nvidia and a somewhat anti-ATI. IIRC, I think his R520 stance was more related to his preference to whatever Nvidia was bringing out at the time. He's obviously got some kind of "special relationship" if the Inq is correct and he's getting half the national allocation on launch day.

Still, 200 cards for the whole country, even at excessive prices seems like a very small amount. If there was more availability, maybe the prices would not be so excessive!

 

I wouldn't say that. He was busy heavily promoting R580 earlier this year on his store/forum.
I think he just promotes what sells well.

 

That would be awesome.

 

That isn't difficult, since G7x is useless at Oblivion:

http://www.firingsquad.com/hardware/radeon_x1950_pro_crossfire/page8.asp

EDIT: according to that page, X1900XT 256MB's min FPS at 1600x1200 no AA is higher than 7900GTX's max FPS.

Jawed

 

I don`t know. Maybe even he forced AA in drivers CP it was disabled but he told about testing with these settings.

 

Long story short, he never said that.

He said something like, when you fix the ratio at 16/32 VS/PS, then pixel shader limited games suffer vs load balancing. Well duh..basically if you fix the ratio to skew too far to VS, it takes away from PS, is all he said.

Most games are presumably much more weighted to PS, so locking 16 ALU's to VS will hurt shading performance, as many of the VS sit idle while the game is shader bottlenecked. That's all he was saying.

 

That's what every sane person out there would think, just analyze current non-unified architectures VS/PS ratio to understand that.

 

simply reprogram the hw scheduler to not subit certain thread types to some ALUs clusters/processors/or whatever they are called.

 

I guess your mileage varies according to the review you look at:

http://www.driverheaven.net/reviews/X1950XTXreview/oblivion.php