Chris123234
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My inner child is desperately hoping that, like most other quiet releases that turn out a surprise, this silence means the return of the R300 legacy.
AMD: R7xx Speculation
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My inner child is desperately hoping that, like most other quiet releases that turn out a surprise, this silence means the return of the R300 legacy.
If there's a GX2 with the GT200 (shrink) then it would obviously exist in a different time frame. Imagine 8800GTX & 9800GX2.
Yep if there is a GX2 version then it would certainly require a shrink. Hell, imagine 2xR600's and how ungodly bad that would be. Almost certainly would require GDDR5 support too to cut memory power draw as well.
It did take a year and a half nearly and a die shrink for the GX2 version of the G80 architecture to come out so it wont be that surprising if true
It did take a year and a half nearly and a die shrink for the GX2 version of the G80 architecture to come out so it wont be that surprising if true
One question still bothering about the truth RV770 480Streams.
A. Is RV770 480 ALU's is packed into groups of 5:1 is 96+384 = 480 streams.
-OR-
B. Is RV770 480 ALU's is packed into groups of 3:1 is 160+320 = 480 streams.
Which solution is more efficient and faster?
I think RV670 with 5:1 ratio sucks? Because even R580 with 3:1 ratio never utilize all 48 pixel shaders at all.
A. Is RV770 480 ALU's is packed into groups of 5:1 is 96+384 = 480 streams.
-OR-
B. Is RV770 480 ALU's is packed into groups of 3:1 is 160+320 = 480 streams.
Which solution is more efficient and faster?
I think RV670 with 5:1 ratio sucks? Because even R580 with 3:1 ratio never utilize all 48 pixel shaders at all.
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RV670's ratio is 4:1.
RV670 Is 4:1+1D
No, you're getting confused with the notation. Thats not what the tex:ALU ratio is looking at.
64 *(4 + 1)=320
320 stream processors = there is only 64 real processors, but each is cable of 5 operations per shader clock.
Shtal, I know the composition perfectly well! 
(and its 64 * (1+1+1+1+1)). But, again, thats not what the tex to ALU ratio is looking at.
Each of those groups of 5 shaders are working on a pixel (in PS ops) and there are 64 of those to 16 textures, hence the ALU:Texture ratio is 4:1.
(and its 64 * (1+1+1+1+1)). But, again, thats not what the tex to ALU ratio is looking at.Each of those groups of 5 shaders are working on a pixel (in PS ops) and there are 64 of those to 16 textures, hence the ALU:Texture ratio is 4:1.
Shtal, I know the composition perfectly well!
Each of those groups of 5 shaders are working on a pixel (in PS ops) and there are 64 of those to 16 textures, hence the ALU:Texture ratio is 4:1.
Ok!
If we revert to RV770 - the final outcome is 480 streams, what type of ratio we really looking at? 3:1, 4:1, 5:1.....
Well, I don't think Dave is going to answer that one.
If rumor speculation says that RV770 is ~25% faster then GF9800GTX - then more efficient way to make it happen is to be (3:1) 160SP's +320 = 480 stream processors.
EDIT: Otherwise with higher ratio then you have to clock your GPU really high to beat GF9800GTX. "Example R600 vs. GF8800GTS-640"
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Shtal, what ratio exactly are you talking about? There's only one ratio and that's ALU:TEX.
What do you mean by (3:1) 160SP's + 320 = 480?
ALU's in RV670 are vec5. This is most likely the case in RV770 as well. This vec5 configuration is sometimes referred to as (4+1) to indicate that one ALU is a bit different from the rest. Is that what you're referring to as a ratio?
Exactly
In that case you shouldnt say 160+320 = 480 (it's confusing and doesn't make sense in context of what you're trying to say).
160 * 3 = 480 is what I think you mean to say. That's doubtful though. 96 * 5 is probably what you're gonna get.
If I'm not mistaken the dual-issue vec3+1 MADD, vec3+1 ADD ALU structure remained the same from R300 all the way to R580. I'd be very surprised if they changed the ALU structure so significantly between R600 and R700.
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