Xbox One (Durango) Technical hardware investigation

[Brad Grenz]

Also the "NDA timing" thing was never more than a conspiracy theory based on a coincidence.

 

[eastmen]

The info albert was talking about from his engineers was the article on digital foundry yesterday.
In that article the ms tech guys said the gpu is from sea islands just like sony.
They did claim they altered the compute units in the gpu but gave no specifics.
They also said they had overhead in the cus for gpgpu.

With it coming straight from ms that the gpu is sea islands that rules out it being volcanic islands.
Now the alterations they claimed to make to the compite units could be from volcanic islands but they didnt specify

Did albert say the article is what he was talking about ?

 

[shredenvain]

Albert hasnt said anything as far as i know about the article but he did say the info would be coming very soon on Twitter friday and then the article came out sunday. In the article they clear up alot of misconceptions about the xbox one and specifically talked about the points albert posted on neogaf.
So im pretty sure that article is what he was refering to.
The article said no 2nd gpu and the gpu was based off of sea islands with modifications to the compute units which they didnt go into detail about

 

[taisui]

Albert hasnt said anything as far as i know about the article but he did say the info would be coming very soon on Twitter friday and then the article came out sunday. In the article they clear up alot of misconceptions about the xbox one and specifically talked about the points albert posted on neogaf.
So im pretty sure that article is what he was refering to.
The article said no 2nd gpu and the gpu was based off of sea islands with modifications to the compute units which they didnt go into detail about

In the article it seemed that there'll be another followup on these details and the esram?

 

[eastmen]

Albert hasnt said anything as far as i know about the article but he did say the info would be coming very soon on Twitter friday and then the article came out sunday. In the article they clear up alot of misconceptions about the xbox one and specifically talked about the points albert posted on neogaf.
So im pretty sure that article is what he was refering to.
The article said no 2nd gpu and the gpu was based off of sea islands with modifications to the compute units which they didnt go into detail about

One could assume sunday would be very soon from fri , but also Wednesday is very soon from Friday.

So I'd wait and see if we get some more info about the hardware. I think we will keep hearing more as we gear up for launch. Just a few days more and I get to play some games no one has heard of yet !

 

[bagofsuck]

We should wait for September 25th and 26.

 

[SlickShoesRUCrazy]

Albert hasnt said anything as far as i know about the article but he did say the info would be coming very soon on Twitter friday and then the article came out sunday. In the article they clear up alot of misconceptions about the xbox one and specifically talked about the points albert posted on neogaf.
So im pretty sure that article is what he was refering to.
The article said no 2nd gpu and the gpu was based off of sea islands with modifications to the compute units which they didnt go into detail about

you know, you are too smart to be posting over at that moronic blog you know.....

 

[onQ]

Yes, whether it is surprising or not, the MS engineer let out the Xbox One GPU is based upon Sea Islands, which belongs to the AMD 8000 series and they haven't been launched yet. I think we should know more in a couple of days.

http://en.wikipedia.org/wiki/Sea_Islands_(GPU_family)

Yes they have

http://www.techpowerup.com/gpudb/1979/radeon-hd-8770-oem.html

http://en.wikipedia.org/wiki/Sea_Islands_(GPU_family)

 

[shredenvain]

Look ive got my day one xbox one almost paid off. Im happy with everything the ms techs explained in the df article. The launch games look great. I think people are putting to much into tflops.
There is no proof they put volcanic islands tech in the xbox one gpu but it has been modified to take advantage of dx 11.2 and it could be possible they put some things from volcanic islands in there.
Its become clear there is not gonna be some last minute revelation in hidden power.

 

[shredenvain]

you know, you are too smart to be posting over at that moronic blog you know.....

Thank you, I started over there because Im into conspiracies but I know when there is enough evidence to give up on them. There are some people that never know when to give up though.

 

[Jay]

Yes they have

http://www.techpowerup.com/gpudb/1979/radeon-hd-8770-oem.html

http://en.wikipedia.org/wiki/Sea_Islands_(GPU_family)

Yea that was my point, rebranding doesn't give or take more information to us apart from that it's not VI based.
It's just another name for same set of cards at the moment.

 

[MarkoIt]

Adding cores never scales linearly. For their statement to be true on a GFLOPS basis (which it probably isn't), a scaling efficiency of 95.6% per core added would provide 12CUs at 853MHz with the same horsepower as 14CUs at 800. At that (bogus) scaling factor, 18 CUs at 800MHz would only be 7.4% faster than 12CUs at 853MHz.

The real scaling factor is guaranteed to be higher than that, but it will still be <1, and the scaling factor probably goes down with increasing cores, since the bottlenecks become even more important. You're going to have a lot more contention for a 256 bit memory bus at 12 cores than at 2. What this means is that in real terms, PS4 does not have, and never had, a 50% GPU advantage. What the actual advantage is, we may never know.

True. Infact it seems that most of the custom work done by Sony over the GNC IP is to increase efficiency and utilizations of the 18 CUs (more ACEs, multiple queues).


Overall, I think it will never be so clear, even in multiplatform title, which has the graphics lead. And considering the really low sales of WiiU, there are huge spaces for both console to do record-shattering sales in their lifespan. I bet that both will break the 100+ million mark, and they could do even more. Which means engines target to shine on both platform. So we should be happy.

 

[Averagejoe]

Adding cores never scales linearly. For their statement to be true on a GFLOPS basis (which it probably isn't), a scaling efficiency of 95.6% per core added would provide 12CUs at 853MHz with the same horsepower as 14CUs at 800. At that (bogus) scaling factor, 18 CUs at 800MHz would only be 7.4% faster than 12CUs at 853MHz.

The real scaling factor is guaranteed to be higher than that, but it will still be <1, and the scaling factor probably goes down with increasing cores, since the bottlenecks become even more important. You're going to have a lot more contention for a 256 bit memory bus at 12 cores than at 2. What this means is that in real terms, PS4 does not have, and never had, a 50% GPU advantage. What the actual advantage is, we may never know.

Edit.

Never mind i understand now.

 

[Shifty Geezer]

Isn't the 7850 at 860mhz with 16 CU like 10% faster than a full 7790 with 14 CU and 1ghz.?

How can the difference be 7% in 14 CU vs 18 CU at 800mhz.?

I think your math is off.

You misread

Adding cores never scales linearly. For their statement to be true on a GFLOPS basis (which it probably isn't), a scaling efficiency of 95.6% per core added would provide 12CUs at 853MHz with the same horsepower as 14CUs at 800. At that (bogus) scaling factor, 18 CUs at 800MHz would only be 7.4% faster than 12CUs at 853MHz.

bkilian is saying MS's maths is off

 

[Averagejoe]

Yes it is a sea islands product as opposed to a southern islands. Supposedly volcanic islands (Hawaii etc) will début this week. MS has a strange NDA timing. Penello said his engineers will reveal certain things this week and the timing of it is after the volcanic islands reveal. However, Bonaire was sold into the channel starting last March.

Why have an NDA on a part based on a part that's already been released 6 months earlier?

I doubt an NDA would stop MS from revealing something powerful or game changing,in fact it goes in AMD best interest as well,or are we going to pretend than MS hide Unified shaders back on 2005 because they could not talk about it because it was something not found on AMD and Nvidia GPU yet.?

Unified shaders didn't show up on PC well after the xbox 360 was launch and MS could not stop talking about it,and hyping how powerful the GPU was i remember it perfectly.

So i don't think that they had something like an advantage that big only to have it hide and not taken advantage of it,in fact Volcanic Island release in a few months,how that compare to xbox 360 GPU tech like Unified shaders.

This is vaporware i think to keep the argument about they having a console on par with the competition which i don't think they have.

 

[Averagejoe]

You misread
bkilian is saying MS's maths is off

Sorry i did big time..

 

[mosen]

Isn't the 7850 at 860mhz with 16 CU like 10% faster than a full 7790 with 14 CU and 1ghz.?

How can the difference be 7% in 14 CU vs 18 CU at 800mhz.?

I think your math is off.

Isn't 7790 bandwidth limited?

7870 XT@600MHz with same Memory (2GB GDDR5@1375MHz), bandwidth, same CPU (Core i7 3770K@ 4.3GHz and 16GB of DDR3 memory@1600MHz) and 32 ROPs is only 24% faster (on average) than 7850@600MHz, Which leads to 97.5% efficiency per CU. However, I don't know whether games that have been used for this purpose are ALU bound or not.

But at the same time this is the best experiment that have been ever done to test Microsoft's claim.

 

[Arwin]

Look ive got my day one xbox one almost paid off. Im happy with everything the ms techs explained in the df article. The launch games look great. I think people are putting to much into tflops.
There is no proof they put volcanic islands tech in the xbox one gpu but it has been modified to take advantage of dx 11.2 and it could be possible they put some things from volcanic islands in there.
Its become clear there is not gonna be some last minute revelation in hidden power.

Don't you think it is far more likely that DirectX 11 was modified to take advantage of the Xbox One?

 

[Gipsel]

7870 XT@600MHz with same Memory (2GB GDDR5@1375MHz), bandwidth, same CPU (Core i7 3770K@ 4.3GHz and 16GB of DDR3 memory@1600MHz) and 32 ROPs is only 24% faster (on average) than 7850@600MHz, Which leads to 97.5% efficiency per CU.

7870 = 20 CUs
7850 = 16 CUs
20/16 = 1.25, that means +25% flops/ALUs/TMUs at the same clock, but the same setup/raster/ROP/memory bandwidth. Getting a 24% speedup under these conditions look suspiciously like either a theoretical or a botched benchmark, in any case one basically completely determined by ALU/TMU throughput. You can't expect this across the board. Even if the 7850 had slower memory at stock speeds and assuming a wide range of benchmarks, it would be an extremely good showing for the downclocked 7870 giving no hint of any scalability issues.

 

[mosen]

7870 = 20 CUs
7850 = 16 CUs
20/16 = 1.25, that means +25% flops/ALUs/TMUs at the same clock, but the same setup/raster/ROP/memory bandwidth. Getting a 24% speedup under these conditions look suspiciously like either a theoretical or a botched benchmark, in any case one basically completely determined by ALU/TMU throughput. You can't expect this across the board. Even if the 7850 had slower memory at stock speeds and assuming a wide range of benchmarks, it would be an extremely good showing for the downclocked 7870 giving no hint of any scalability issues.

7870 XT = 24 CUs ==> 24/16= 1.5 ...