Xbox One (Durango) Technical hardware investigation

[taisui]

What Penello said was just PR bullock, how do you qualify and compare graphics that are "30% better" or "on par?" That's different than what the earlier poster was implying, that MS spins on the technical details, like X1 CPU is faster than PS4, or that PS4 has bad bus design. prove me wrong.

 

[messyman]

Albert is quite famous for making statements like that on neogaf.

see my statements the other day caused more of a stir than I had intended. I saw threads locking down as fast as they pop up, so I apologize for the delayed response.

I was hoping my comments would lead the discussion to be more about the games (and the fact that games on both systems look great) as a sign of my point about performance, but unfortunately I saw more discussion of my credibility.

So I thought I would add more detail to what I said the other day, that perhaps people can debate those individual merits instead of making personal attacks. This should hopefully dismiss the notion I'm simply creating FUD or spin.

I do want to be super clear: I'm not disparaging Sony. I'm not trying to diminish them, or their launch or what they have said. But I do need to draw comparisons since I am trying to explain that the way people are calculating the differences between the two machines isn't completely accurate. I think I've been upfront I have nothing but respect for those guys, but I'm not a fan of the mis-information about our performance.

So, here are couple of points about some of the individual parts for people to consider:

• 18 CU's vs. 12 CU's =/= 50% more performance. Multi-core processors have inherent inefficiency with more CU's, so it's simply incorrect to say 50% more GPU.
• Adding to that, each of our CU's is running 6% faster. It's not simply a 6% clock speed increase overall.
• We have more memory bandwidth. 176gb/sec is peak on paper for GDDR5. Our peak on paper is 272gb/sec. (68gb/sec DDR3 + 204gb/sec on ESRAM). ESRAM can do read/write cycles simultaneously so I see this number mis-quoted.
• We have at least 10% more CPU. Not only a faster processor, but a better audio chip also offloading CPU cycles.
• We understand GPGPU and its importance very well. Microsoft invented Direct Compute, and have been using GPGPU in a shipping product since 2010 - it's called Kinect.
• Speaking of GPGPU - we have 3X the coherent bandwidth for GPGPU at 30gb/sec which significantly improves our ability for the CPU to efficiently read data generated by the GPU.

Hopefully with some of those more specific points people will understand where we have reduced bottlenecks in the system. I'm sure this will get debated endlessly but at least you can see I'm backing up my points.

I still I believe that we get little credit for the fact that, as a SW company, the people designing our system are some of the smartest graphics engineers around – they understand how to architect and balance a system for graphics performance. Each company has their strengths, and I feel that our strength is overlooked when evaluating both boxes.

Given this continued belief of a significant gap, we're working with our most senior graphics and silicon engineers to get into more depth on this topic. They will be more credible then I am, and can talk in detail about some of the benchmarking we've done and how we balanced our system.

Thanks again for letting my participate. Hope this gives people more background on my claims.

http://www.neogaf.com/forum/showpost.php?p=80951633&postcount=195

 

[taisui]

thanks, *face palm

 

[Lalaland]

Any chance of editting in quote tags messyman? It seems as if you're apologising for your posts rather than quoting Penello.
Edit: Cheers messyman!

Thanks for digging this up by the way I'd forgotten he'd doubled down on his "30% no way" comments with more daft sounding 'technical points'.

 

[pjbliverpool]

I find it comical that Penello cites DX as an example of Microsoft's l33t software skills considering what a joke Mantle has shown it to be.

Give us a streamlined DX12 that performs on par with Mantle Microsoft, then I'll listen.

 

[messyman]

Thanks for the edit, Shifty.

 

[Scott_Arm]

I find it comical that Penello cites DX as an example of Microsoft's l33t software skills considering what a joke Mantle has shown it to be.

Give us a streamlined DX12 that performs on par with Mantle Microsoft, then I'll listen.

While DX can probably be optimized, Mantle has the benefit of being AMD specific, which gives it an inherent advantage in terms of performance optimization.

 

[AlphaWolf]

While DX can probably be optimized, Mantle has the benefit of being AMD specific, which gives it an inherent advantage in terms of performance optimization.

AMD GCN specific.

 

[mosen]

As Zachriel said, the broken down CPU+GPU results were given to Gamingbolt directly. There's no real reason to advertise the CPU or GPU only times on the official website because they're not really relevant on their own. They are only sub-components of the total decode time (if considering the CPU+GPU time).

It seems the consoles are being held back by the CPU component of the CPU+GPU decode while the PC is being held back by the GPU component - likely because of PCI latency. However CPU+GPU decode is obviously still a lot faster than CPU decode alone on the PC since the CPU portion of the work is a lot smaller.

There is noting exclusive to gamingbolt except CPU & GPU model/spec they have used. But what they write on their site is completely irrelevant to what I already can see on official site. All PS4s or X1s specs are the same but the results on this two sites are different (for both consoles), so one of them should be wrong and there is no way for official site to be wrong specially when they said to gamingbolt that they already corrected the incorrectly phrased part :

A developer from Rad Game Tools got in touch with us clarifying that the numbers were incorrectly phrased on their website [which they have corrected now].

http://gamingbolt.com/new-benchmark...ay-4k-video-frames-faster#BJzorBArCDEz2k2V.99

 

[pjbliverpool]

The sites don't disagree.

http://www.radgametools.com/bnkmain.htm

it can play 4K video frames (3840x2160) in 4 ms PCs and 11 ms PS4/Xbox One using the CPU only (or 1.4 ms PC and 2.3 ms PS4/Xbox using GPU acceleration)!

http://gamingbolt.com/new-benchmark...y-4k-video-frames-faster#BJzorBArCDEz2k2V.99:

PC (2.8Ghz Core i5 with 4 cores and AMD R9 290x): CPU: 1.3 ms. GPU: 1.4 ms.
PS4: CPU 2.3 ms. GPU: 1.6 ms.
Xbox: CPU 2.3 ms. GPU: 2.3 ms.

Where's the difference?

 

[taisui]

The sites don't disagree.

http://www.radgametools.com/bnkmain.htm



http://gamingbolt.com/new-benchmark...y-4k-video-frames-faster#BJzorBArCDEz2k2V.99:



Where's the difference?

Why anyone would bother looking at anything but the official source beats me.

 

[pjbliverpool]

Why anyone would bother looking at anything but the official source beats me.

Unless gamingbolts numbers are outright made up they do provide some interesting additional detail.

 

[taisui]

Unless gamingbolts numbers are outright made up they do provide some interesting additional detail.

RAD phrased the numbers in a way that Gamingbolts had misunderstood, and RAD had since made clarifications.

First, it proclaims the speed of Bink 2 thanks to “multi-core scaling and SIMD design (up to 70% of the instructions executed on a frame are SIMD). It is really fast – it can play 4K video frames (3840×2160) in 4 ms on PCs and 11 ms on Sony PS4 or Xbox One using the CPU only (or 1.4 ms and 2.3 ms using GPU acceleration)!”

You are bound by the slowest component, in this case, the 2.3ms CPU time, meaning that you best you can do is still 2.3ms per frame. The confusion is that the original phrase made it sound like it's 1.4ms for the PS4 and 2.3ms for the X1, per frame decoded. The X1 GPU has less CUs, being slower is not interesting, it's expected.

 

[pjbliverpool]

You are bound by the slowest component, in this case, the 2.3ms CPU time, meaning that you best you can do is still 2.3ms per frame. The confusion is that the original phrase made it sound like it's 1.4ms for the PS4 and 2.3ms for the X1, per frame decoded. The X1 GPU has less CUs, being slower is not interesting, it's expected.

But the breakdown of the PC information, and especially what it tells us about the benefits of HSA IS interesting.

 

[DrJay24]

You are bound by the slowest component, in this case, the 2.3ms CPU time, meaning that you best you can do is still 2.3ms per frame. The confusion is that the original phrase made it sound like it's 1.4ms for the PS4 and 2.3ms for the X1, per frame decoded. The X1 GPU has less CUs, being slower is not interesting, it's expected.

I guess you don't recall the 14+4 debates? To some more CUs does not mean much more performance, even MS implied as much. But yes, more CUs means a faster GPU, I'm glad everyone can finally agree on something so basic.

 

[function]

I guess you don't recall the 14+4 debates? To some more CUs does not mean much more performance, even MS implied as much. But yes, more CUs means a faster GPU, I'm glad everyone can finally agree on something so basic.

The debate was never so simplistic.

How much faster depends on lots of things, such as the rest of the system and what you're trying to do.

If the issue were CUs alone, the PS4 would not be seeing the kind of performance advantages it sometimes does.

 

[taisui]

But the breakdown of the PC information, and especially what it tells us about the benefits of HSA IS interesting.

mind quoting the part about HSA?

I guess you don't recall the 14+4 debates?

having unified cores only to divide them up for specific purposes, yea, how low does this have to go?

 

[DrJay24]

The debate was never so simplistic.

How much faster depends on lots of things, such as the rest of the system and what you're trying to do.

If the issue were CUs alone, the PS4 would not be seeing the kind of performance advantages it sometimes does.

http://www.eurogamer.net/articles/digitalfoundry-vs-the-xbox-one-architects

"Every one of the Xbox One dev kits actually has 14 CUs on the silicon... And we actually saw on the launch titles... we found that going to 14 CUs wasn't as effective as the 6.6 per cent clock upgrade that we did."

"Sony was actually agreeing with us. They said that their system was balanced for 14 CUs. They used that term: balance. Balance is so important in terms of your actual efficient design. Their additional four CUs are very beneficial for their additional GPGPU work. We've actually taken a very different tack on that. The experiments we did showed that we had headroom on CUs as well.

IMO those two statements (said back to back in the interview) are trying damn hard to imply their bump in clock to 12CUs is better than 18CUs. Of course you can say anything you want until the games come out.

 

[imaxx]

Actually
Durango was stated as having 30 GB/s in coherent bandwidth, or 3x for GPGPU.

...aaah, you were referring about that, got it - fine.

Still, while coherent BW is surely useful, what's the (tangible) benefit if your effective usage is much lower. Do you really need to exchange > 100MB/frame?

 

[taisui]

http://www.eurogamer.net/articles/digitalfoundry-vs-the-xbox-one-architects





IMO those two statements (said back to back in the interview) are trying damn hard to imply their bump in clock to 12CUs is better than 18CUs. Of course you can say anything you want until the games come out.

there are like 500 words in between the 2 quotes, I feel you are taking them out of context. Besides, isn't it a Sony leak that actually said 14CU at balance? no?