Xbox One (Durango) Technical hardware investigation

[Tchock]

Right, but this is 4x256bit GDDR3 so you'll have substantially more pads.

That would be a 1024-bit interface.

refer here

 

[BRiT]

Woops, got the esram and gddr interface widths mixed up.

So looks like somewhere around ~190mm^2 is the pad limited going off of RV670. So probably wont hit that until the 14nm shrink.

 

[Dave Baumann]

http://images.anandtech.com/doci/6209/TahitiDieShot.jpg

FYI - that's Tahiti at about 358mm^2. Its reasonably clear where the 384b interface is...

 

[MrFox]

Is there any difference in pad requirements between GDDR3 and DDR3, for the same width?

 

[XpiderMX]

"We've made some alterations to the CPU clusters to support coherent bandwidth between clusters...and other processors," Sell said.

The graphics processor supports DirectX 11.1, which is Microsoft's graphics engine that will power games. Microsoft calls the engine 1-plus, a reference to unique control processor features for custom graphics and processing in the Xbox graphics core. "These have been customized to significantly reduce the amount of time, the amount of work, that the CPU has to spend when assembling graphics commands," Sell said. One unique aspect of the chip is a shared memory pool that can be accessed by CPUs, GPUs and other processors in the system. Typically, GPUs and CPUs have different memory systems, but the new features increase the overall addressable memory in the Xbox One. The GPUs and CPUs have also been modified to enable shared memory.Shared memory is also part of a specification being pushed by the HSA Foundation, which wants to blur the line between GPU and CPU memory to make programming easier. AMD is one of the founding members of the HSA Foundation, though Sony is also a member, which suggests that shared memory may also be part of PlayStation 4.

"We can let developers have access to direct programming on GPU without a lot of overhead," Sell said.

Overall, the system has been designed to balance bandwidth with the power requirements.

"An important aspect of that is letting CPU and GPU share memory spaces," Sell said.The coherency connections are a derivative of AMD's years-old HyperTransport technology. The bandwidth can sustain data transfers of 30GB per seconds. However, the data transfers vary depending on the component and also the distance between parts.The chip will be made by Taiwan Semiconductor Manufacturing Co. (TSMC) using the 28-nm process, Sell said.

http://www.itworld.com/hardware/370538/xbox-one-will-have-high-performance-custom-chip?page=0,0

It looks like HSA complaint.

 

[Scott_Arm]

Unique control processor features for custom graphics and processing in the Xbox graphics core?

 

[bagofsuck]

i want to know about the CPU speed,was 1.6 GHz ever confirmed?

 

[Esrever]

i want to know about the CPU speed,was 1.6 GHz ever confirmed?

nope, neither consoles will likely reviel clock speeds until someone hacks them or leaks happen. I doubt they will even be relieved after launch.

 

[Rangers]

BTW, it was said, I think I read it on GAF? and I want to say maybe it came from bkilian here? That the audios processor/SHAPE came about when MS went to the Xbox team and said something like "we have a bunch of "free" transistors, what do you guys want to do with them"?

That obviously is rather provocative. What is the thinking there? Free transistors and why? Why not used on more graphics then?

It sort of reminds me how it was said Intel integrated GPU's came about because they were I/O limited, so they in essence had free area on their CPU's which they decided to fill up with graphics.

 

[AlNom]

That obviously is rather provocative. What is the thinking there? Free transistors and why? Why not used on more graphics then?

Depends on how much space there was and what the layout was permitting (i.e. think Tetris). Compute units and render back ends aren't exactly something you throw into a small area without implications (e.g. hooking up RBEs to the scratchpad to scale the bandwidth I/O etc, existing layout of CUs may not be conducive towards adding just one more, plus they aren't insignificant themselves if you've seen the die shots of 7xxx).

 

[Jay]

That the audios processor/SHAPE came about when MS went to the Xbox team and said something like "we have a bunch of "free" transistors, what do you guys want to do with them"?

That obviously is rather provocative. What is the thinking there? Free transistors and why? Why not used on more graphics then?

My guess is, if that was the case it went like this:
Put aside space for Kinect stuff, and realised had spare transistor capacity left once it was all designed etc.

It may not even have been enough transistors for CU, or even in a suitable location.

But fixed logic is faster and needs less transistors, so why not use it to remove sound from the cpu and/or cu's? Get more bang for your transistor buck probably.
All games may not use it to it's full potential, but it's still freeing up other resources regardless.

 

[XpiderMX]

I'm guessing that the 16GB rumor was a confusion because the 8GB DDR3 and the 8GB flash memory.

 

[tunafish]

Woops, got the esram and gddr interface widths mixed up.

Oh, it's also not GDDR, it's just DDR.

 

[bkilian]

BTW, it was said, I think I read it on GAF? and I want to say maybe it came from bkilian here? That the audios processor/SHAPE came about when MS went to the Xbox team and said something like "we have a bunch of "free" transistors, what do you guys want to do with them"?

That obviously is rather provocative. What is the thinking there? Free transistors and why? Why not used on more graphics then?

It sort of reminds me how it was said Intel integrated GPU's came about because they were I/O limited, so they in essence had free area on their CPU's which they decided to fill up with graphics.

The custom audio chip designed by MS and Tensilica had "free" transistors. I don't know if that means that the way the blocks were organised they had square mm free, or if the price they were paying was the same up to X amount of transistors or what. They could not be used for graphics, physics, or anything else, because they're not in the right part of the APU, and they have to use the AXI bus to communicate with the rest of the system. The right thing, and the only thing, to do with them was use them for audio tasks.

 

[grndzro]

The custom audio chip designed by MS and Tensilica had "free" transistors. I don't know if that means that the way the blocks were organised they had square mm free, or if the price they were paying was the same up to X amount of transistors or what. They could not be used for graphics, physics, or anything else, because they're not in the right part of the APU, and they have to use the AXI bus to communicate with the rest of the system. The right thing, and the only thing, to do with them was use them for audio tasks.

Transistors have no effect on the chip price in and of themselves.
The price to fab a chip is it's area. they pay per silicon mm.

Large complex chips can have much higher failure rates per chip
which are either absorbed by the customer or by the foundry.

Costs being absorbed by the foundry dont happen as much now because there is no shortage of customers. Sometimes early in a process node during debugging foundry's make deals to pay for defective chips.

 

[Jay]

I read it as area that was allotted to "MS and Tensilica" for the Kinect stuff.
No point leaving a blank bit of silicon there when you could put shape in there.

 

[MrFox]

I'm guessing that the 16GB rumor was a confusion because the 8GB DDR3 and the 8GB flash memory.

The 16GB rumor was most probably a feedback loop that started with fun speculation about what they could or couldn't do. Those pesky feedback loops happened very often in the last 12 months... about everything

 

[Cyan]

BTW, it was said, I think I read it on GAF? and I want to say maybe it came from bkilian here? That the audios processor/SHAPE came about when MS went to the Xbox team and said something like "we have a bunch of "free" transistors, what do you guys want to do with them"?

That obviously is rather provocative. What is the thinking there? Free transistors and why? Why not used on more graphics then?

It sort of reminds me how it was said Intel integrated GPU's came about because they were I/O limited, so they in essence had free area on their CPU's which they decided to fill up with graphics.

I think bkillian and his team had plenty of free transistors.

For those who are technologically minded, which is the typical B3D former, the Xbox One's 5 billion transistors are enough to populate about 2.2 million Intel 4004 processors.

sebbbi, the links you shared are mainly related to articles talking about Tiled Resources. Does BF4 feature Tiled Resources? Just curious....

 

[Love_In_Rio]

I think bkillian and his team had plenty of free transistors.

For those who are technologically minded, which is the typical B3D former, the Xbox One's 5 billion transistors are enough to populate about 2.2 million Intel 4004 processors.

sebbbi, the links you shared are mainly related to articles talking about Tiled Resources. Does BF4 feature Tiled Resources? Just curious....

Why should Sebbi know about BF4,?. Are you confusing him with Repi?. Sebbi knows for sure about "Trials Evolution".

 

[Cyan]

Why should Sebbi know about BF4,?. Are you confusing him with Repi?. Sebbi knows for sure about "Trials Evolution".

(edited part) You are right, he is one of the developers of the brilliant Trials Evolution. Anyway, sebbbi is very technologically minded and he is probably working in advanced games.

All I know is that despite his saying he is one of the main programmers of Trials games, he is also involved in other games afaik.