Digital Foundry Microsoft Xbox Scorpio Reveal [2017: 04-06, 04-11, 04-15, 04-16]

[VitaminB6]

Lack of FP16 is curious. Also closes the performance delta potentially. What with this and the ID buffer, it'll be very interesting how the two system compare. VRR certainly makes Scorpio the choice of the elite gamer though.

Mid gen boxes ended up being a lot more interesting than we feared!

Do we really understand the significance of fp16 on performance? Maybe it simply was not crucial or that beneficial... Certainly MS had this available as an option and decided it was not worth the floor plan space or cost.

 

[mosen]

Finally the article is released...

A bit of a shame on the DR FP16, but using the 30% improvement developer number (from sebbi I think?) should still place the Scorpio above 4Pro given the 42% higher 6TF over 4.2TF specs.

30% overall improvement or only in some specific process?

 

[Shifty Geezer]

It is not lack of fp16.

Is it really not that obvious I meant the double rate option given we were talking about Scorpio lacking double-rate FP16 and that being the only advantage PS4 has in the context of comparing the two machines? :shrug:

I'll edit my post to make that clear.

 

[AlNom]

Would have been better if they had detailed the feature set really. There's ambiguity to me with even Tonga features.

Edit: i.e. It looks like they grabbed features outside of the compute processing, thus ensuring compatibility on what things are run vs how they are shuffled around the processor.

 

[Ike Turner]

30% overall improvement or only in some specific process?

30% on a specific process...and using FP16 not specifically Double-Rate FP16 so this would apply To Scorpio to..
http://www.frostbite.com/2017/03/4k-checkerboard-in-battlefield-1-and-mass-effect-andromeda/

Another optimization was the usage of FP16 GCN instructions in our checkerboard resolve shader. PS4™Pro has support for FP16, and we used it throughout the checkerboard resolve shader. The largest benefit was the ability to greatly lower our LDS memory usage. This resulted in a 30% performance improvement in the resolve shader.

In the grand scheme of things...this isn't much at all...and would apply to Scorpio.

 

[mrcorbo]

Another optimization was the usage of FP16 GCN instructions in our checkerboard resolve shader. PS4™Pro has support for FP16, and we used it throughout the checkerboard resolve shader. The largest benefit was the ability to greatly lower our LDS memory usage. This resulted in a 30% performance improvement in the resolve shader.

Huh. Good catch @Ike Turner.

 

[mpg1]

I'm still skeptical we will even see much checkerboarding techniques used on Scorpio...it mean it's ultimately up to the developer but it seems Microsoft created Scorpio in mind with scaling Xbox One games to 4K. I'd say we would see techniques like dynamic res before we see checkerboard.

 

[AlNom]

Dynamic res would be more flexible and portable, certainly.

What would be nice is if MS developed something like nVidia Ansel for those folks who like taking screenshots, and offer a standard library of sorts for developers to plug into their games.

 

[chris1515]

https://www.google.ch/amp/www.eurog...6-hands-on-with-mantis-burn-racing-on-ps4-pro

But dual fp16 helped mantis burn racing developer to have 4k native on PS4 Pro coming from a 1080p PS4 title but loosing 2xMSAA of the PS4 version.

Of course, we already knew that the Pro graphics core implements a range of new instructions - it was part of the initial leak - but we didn't really know exactly what they could actually do. As we understand it, with the new enhancements, it's possible to complete two 16-bit floating point operations in the time taken to complete one on the base PS4 hardware. The end result from the new Radeon technology is the additional throughput required to making Mantis Burn Racing hit its 4K performance target, though significant shader optimisation was required on the part of the developer.

It was before the gamasutra Mark Cerny Interview.

 

[HBRU]

It seems engines will use more and more this FP16x2 as also Switch has and future AMD cards too... (as NVIDIA)... will see the differences between Scorpio and Ps4pro

 

[Ike Turner]

https://www.google.ch/amp/www.eurog...6-hands-on-with-mantis-burn-racing-on-ps4-pro

But dual fp16 helped mantis burn racing developer to have 4k native on PS4 Pro coming from a 1080p PS4 title but loosing 2xMSAA of the PS4 version.



It was before the gamasuta Mark Cerny Interview.

I'm fairly certain that using double-rate fp16 on some shaders isn't the primary factor for the jump from 1080P to 4K...especially on a game that doesn't really have much going on display...and the Eurogamer quote is factually wrong:

it's possible to complete two 16-bit floating point operations in the time taken to complete one on the base PS4 hardware

PS4 (GCN1/2) doesn't have support for single-rate 16Bit ops..

 

[AlNom]

He means compared to a single op ( which is naturally only fp32) on PS4.

 

[ramr]

The details of the simulation process are interesting, as is how much of that time was spent on insuring full BC with Xbox One. Sounds like the bulk of the development effort for Scorpio was spent on making the required development process for Scorpio as much like, "Do what you're already doing, but when you get to the end hit the '4K' button instead of the '900p/1080p' button." as possible. Then it's up to the developers to determine if it's worth putting in more effort than that.

The simulation material was very interesting. I think folks that haven't used extensive simulation for decision making may be sleeping on the value that this has. MS stated that they essentially see significant IPC gains in Scorpio compared to PC (unknown whether that is Polaris, NVidia, or Vega - likely Polaris). I just wonder in this context what "significant" means. I could see 10% being significant or something like 30%+. The 1 data point that we have is the Scorpio outperforms (perhaps slightly) 6.5 NVidia TFs.

 

[Ike Turner]

I'm still skeptical we will even see much checkerboarding techniques used on Scorpio...it mean it's ultimately up to the developer but it seems Microsoft created Scorpio in mind with scaling Xbox One games to 4K. I'd say we would see techniques like dynamic res before we see checkerboard.

MS loves Dynamic Resolution, so much that they helped DICE develop it for Frostbite (and they have one of the best implementation in Halo 5)

 

[chris1515]

I'm fairly certain that using double-rate fp16 on some shaders isn't the primary factor for the jump from 1080P to 4K...especially on a game that doesn't really have much going on display...and the Eurogamer quote is factually wrong:


PS4 (GCN1/2) doesn't have support for single-rate 16Bit ops..

The Dev only talk about this and nothing else in the article and it was not a public information before Mark Cerny talked about it...

The confirmation arrive with the gamasutra interview.

 

[chris1515]

At the PlayStation Meeting, Sony staff told me that the enhancements made to the core hardware go beyond the checkerboard upscaling technology, and the new instructions certainly support Mark Cerny's assertion that the PS4 Pro possesses graphics features not found in AMD's current Polaris line of GPUs. Interesting stuff, and we look forward to learning more.

It was an information under NDA...

 

[mpg1]

Honestly what was Microsoft thinking. It would have been way better to release a 4.3Tflop console with a bunch of secret sauces. Idiots.

 

[Ike Turner]

The Dev only talk about this and nothing else in the article and it was not a public information before Mark Cerny talked about it...

The confirmation arrive with the gamasutra interview.

There's no dev talking here. It's all Richard Leadbetter reporting on what he might have understood. And there's only one mention of DR FP16 in the whole thing. I wouldn't concluded anything based on that..as a matter of fact the whole thing is a whole bunch of words that don't explaining anything about how things where achieved... They used Packed FP16 for a bunch of shaders.. that's Cool... I guess but that sure as hell didn't magically enable them to jump from 1080P w/2XMSSA to 4K no-MSSA.

 

[chris1515]

There's no dev talking here. It's all Richard Leadbetter reporting on what he might have understood. And there's only one mention of DR FP16 in the whole thing. I wouldn't concluded anything based on that..as a matter of fact the whole thing is a whole bunch of words that don't explaining anything about how things where achieved... They used Packed FP16 for a bunch of shaders.. that's Cool... I guess

It was not a public information at the moment. It is the Mantis burn racing who talk to him about this information and it was one element to help have a 4k native resolution coming from a 1080p 2xMSAA...

And it is very clear reading the article...

 

[Ike Turner]

It is the Mantis burn racing who talk to him about this information and it was one element to help have a 4k native resolution coming from a 1080p 2xMSAA...

And it is very clear reading the article...

Exactly. One tiny element compared to dropping 2XMSAA for example and most probably tons of other optimisations.