a discusion on yukon roadmap got me thinking
take alook a the road map almoast all has been correct or is the process still (ie FORTALEZA). only this yukon road map shows the second gpu.
Microsoft Roadmap, the XBox 720 and more - Leak - Beyond3D Forum
now look to vg leaks for GPU
World Exclusive: XBox One (Durango) GPU detailed - VGLeaks
insiders said it was right, but missing 1/2, multiple other sources confirm. vgleaks is almoast the same as yukon except gives more detail on the interconnection of all the components, and details the gpu components.
now look to hot chips
XBox One details in pictures | SemiAccurate
tech pros say its very powerful, more powerful than thought, insiders say still only 1/2.
so i think put the 2 1/2's together.
look at vgleaks gpu detail, 1 command processer, 1 graphics processer on the gpu this is correct. now look to hot chips 2 command processers 2 graphics processers, this is also correct because there are at least 2 "gpus".
look closely at the hot chips slides, notice they use 3 diffrent color boxes to describe 1 gpu. that doesnt make sense, why not put it all in one block, of same color, or make all 3 boxes same color.
(look on otherslides for hot chips, look at audio slide each seperate componet a diffrent color the DSP is blue the scaler is yellow the 2 vectors are both red. all the ram is shaded grey)
because its not just 1 gpu look at the memory interconnects, orange and pink blocks have acess to memory not yellow block.
3 seperate processers = 1 gpu. (also very easy to make mistake for potential leaker)
orange = dgpu 12 SC 1.7 g primitives(polygons) (More on this below)
Pink = gpgpu 12 SC 1.31 Tflops
yellow = custom processer (DX11 Core) for render and shading
notice the orange and pink get data from ram and the command processers, and the yellow only gets info from pink or orange, then outputs to memory.
well now we think ok maybe a coincidence
but then we find the size of the die is 150mm2 bigger than ms says, hmm an extra 150mm2 not big enough for a big gpu but just enough space for 12 additioanl sc. addianaly ms reavels 47mbs of Esram, hmm an extra 11 mb, for what, just enough for another gpu, or in this case mor sc's.
also ties in with rumors about 24-28 SC, if you think in terms of 1 big gpu that has been partitioned to 12/12 cores on each side., also would tie in with 768 ops. as revealed in tech panel both gpus run at same clock because its one big gpu of 24 sc, each side has 768 ops also fits with hot chips info of custom graphics processer.
now also makes since if you think about it as 1 big gpu of 24 sc can produce XX tflops in old fashioned way will produce xx more Tflop in new partitioned way as gpgpu increases the efficiency of the DGPU, also if the partition is flexible it can move and allow more sc for for gpgpu when needed, and more for dgpu when needed. also if partitioned it would make sense to have a compute and graphics controller on each side of the partition, expecialy if flexible.
ananother thing to tie in is the cpu 2 - 4 core modules. 1 four core module for each 1/2 of the gpu.
remember each 4 cores does 24 ops, more than enough for cpu.
so then look back at yukon look specifically at gpus, main gpu = 48 alu, app gpu = 64 alu. app alu = 30% more alu than main
1.31tflops * 30% =1.7 tflops dgpu, or orange box does 1.71 gprimitives
perhaps ms met there goal with only 12 sc because they off loaded some data processing to the 3rd dx11 core.
all also ties in well with 2.4 - 3 tflop performance being discussed and rumored.
and that third processer in the GPU could be where the special stuff is. that PCS wont be able to do for 5 years, ray/path tracing ect...
the DX11 core. where the hardware tiling occurs
so essential i speculate 1- 8 core jaguar++, 1- 24 sc GPU partitioned to 12 GPGPU cores, and 12 DGPU Cores, along with 15 custom co processers, one of them being linked directly to the GPUs for post processing(DX11)
custom processers
1 Physics
2 geometry
8 audio
2 video
1 Move engine
1 dx11 core
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