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Why did Sony stay with 36CUs for the PS5?

but the thing is, increasing clock speeds is the easiest way to do just that.

was PS5 targetting 2.23ghz from the start? we wont know. but let see where Amd 7nm+ rdna2 ends up in their clocks. :messenger_smiling_with_eyes:
Keep in mind Sony was helping AMD with Navi from the very beginning. Those clocks have always been the focus. Mark Cerny, even said himself that they could clock higher, but would run into logic issues.

Because of this

200809074720944084.png


Now, we know PS5 can't reach XSX on GPU performance raw expect some engine prefer frenquency over CU. (depending how dev make the game).
The only interesting thing on PS5 over XSX is the AMD SmartShift (CPU can help GPU and vice versa)

This is not exactly a fair comparison to what the PS5 will be capable of considering they're looking at RDNA1. Not to mention all the customization done within their GPU among other things such as the custom geometry engine, cache scrubbers (keeping CU saturated), etc. Digital Foundry is grasping at straws here. Anyway, yeah, SmartShift can occur hundreds of times per second, so it will be interesting to know what kind of performance uplift this causes.
 

jonnyp

Member
If you want the most powerful console you get the xbox series x pure and simple. Lots of people care about this sort of thing ( powerful cars, motorbikes, phones etc). Power is everything imo. Combine that with consumer friendly practices and the xbox game pass and it becomes impossible to justify a ps5.

Tagline checks out.
 

freefornow

Member
It stems from Mark Cerny's love of old English money as he see all architecture in Shillings and pence, related to his need to keep change for the bus.

36 aka 3 and 6 aka PS5.
"You try and tell the young people of today that, and they wont believe you!"
 

PaintTinJr

Member
They are bigger because RDNA 2 CUs are bigger than GCN CUs. This isn’t unique to PS5
Yeah, but I think the PS5 CU workgroups will be bigger because of the cache scrubbers - as that surely requires some additional unit to liaise with the memory controller that brings data to and from the unified ram to the L2 cache, wouldn't you think?

Also - can't remember if it was in an AMD, DF, Cerny or UE5 demo deep dive video, interview, technical docs or tweets, I watched/read. or if I've imagined it :pie_thinking: - but I've got it in my head that the PS5 GPU has 3 levels of cache hierarchy (L0, L1 and L2) - and that it might be custom to the PS5 because of the scrubbers. IIRC an L0 cache has been added to avoid CU WGPs thrashing the L1 cache and being forced to wait when the shared L1 cache gets updated. IIRC the 3 tier system allows the L2 cache to be updated , the L1 caches to partially change as needed, and the L0 cache to be used, uninterrupted until data needs move to/from the L1 cache. Hopefully I haven't imagined that, and some else remembers the same thing.
 

MaulerX

Member
52CU's vs 36CU's


This is a staggering difference when it comes to Ray-Tracing. It's an advantage that will be easily visible in multiplats games.
 

SF Kosmo

Al Jazeera Special Reporter
Ps5 and XSX are not in the same family so your post comparison is irrelevant.

Ps5 has direct apis, XSX has abstract apis.
Ps5 has custom Geometry engine, patents on foveated randering type VRS linked with different type of mesh shaders
Ps5 has cache scrubbers and coherency engine
XSX will use mesh shaders and VRS.
XSX has more CUs clocked 20 % less.

The apis and clock speed alone will close the 18 % gap, dont be so sure lol. NO I did not say ps5 was more powerful, I said gap will be minimal.

And ps5 first party will stand out.

There is more to be revealed about ps5 and XSX, they will be more different in many instances.
Yeah I think apart from the digital foundry microscopes you're not gonna see a big difference between the two for most multiplatform titles, especially once we get a year in or so and people understand hot to optimize for the hardware.
 

PaintTinJr

Member
52CU's vs 36CU's


This is a staggering difference when it comes to Ray-Tracing. It's an advantage that will be easily visible in multiplats games.
Even though the point will be sort of moot, because hardware accelerated RT - instead of UE5 demo ACE software based RT will be used for 70-90% scene (eg background) - will almost certainly be reserved for just the main foreground scene assets in most games, the theoretical difference is still 10TF versus 12TF.

Although, in reality between the cache scrubbers, faster cache, and the faster "command buffer" which Cerny explicitly mentioned in the Road to PS5, the higher the ray density per frame - that exceeds the XsX command buffer rate and/or exceeds the L2 cache data - the PS5 will have an advantage of being able to partially update the cache without stalling the workload, and will be able to launch more workloads. So in all likelihood it is better at both hardware and software RT in real-world situations.

Full RT games by third parties are unlikely to happen anyway, because it would effectively be a generation exclusive + PC top tier niche game - which limits their opportunities on the license free PC market.
 

MaulerX

Member
Even though the point will be sort of moot, because hardware accelerated RT - instead of UE5 demo ACE software based RT will be used for 70-90% scene (eg background) - will almost certainly be reserved for just the main foreground scene assets in most games, the theoretical difference is still 10TF versus 12TF.

Although, in reality between the cache scrubbers, faster cache, and the faster "command buffer" which Cerny explicitly mentioned in the Road to PS5, the higher the ray density per frame - that exceeds the XsX command buffer rate and/or exceeds the L2 cache data - the PS5 will have an advantage of being able to partially update the cache without stalling the workload, and will be able to launch more workloads. So in all likelihood it is better at both hardware and software RT in real-world situations.

Full RT games by third parties are unlikely to happen anyway, because it would effectively be a generation exclusive + PC top tier niche game - which limits their opportunities on the license free PC market.



I'm just going to leave this here and people can make what they want of it... A respected era insider, who also happens to be a mod there, left this nugget last night:




"I'm not going to say too much, but from some murmurings I've been hearing, I'll just say I suspect this topic is going to age "interestingly" when a few more details on both platforms are revealed.

I mean this in a few more ways, but to give the broadest idea, I'll just say the Xbox X is by far more powerful than the PS5 if we're just talking raw power, multi-platform games will run better on Xbox X is something people are going to have to prepare themselves for. Add to this Microsoft are ready to lowball Sony when it comes to price. They can more easily make a sacrifice and get back profits from Game Pass than console sales than Sony can from that comparatively."
 

njean777

Member
The Xbox division can’t take any loses “again”. Don’t think that Microsoft’s money will go to their gaming division. Please understand that.

I never they would, they can if they want is the truth. They are one of the richest companies in the world. If they really wanted to they could undercut Sony 150$ Per console and be just fine. Not that they will, but they could. People seem to forget that Sony is not like MS when it comes to money. If MS wanted to really sell these consoles they will make it happen no matter what and they could afford it. Simple as that
 
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njean777

Member
I never said it would, they can if they want is the truth. They are one of the richest companies in the world. If they really wanted to they could undercut Sony 150$ Per console and be just fine. Not that they will, but they could. People seem to forget that Sony is not like MS when it comes to money. If MS wanted to really sell these consoles they will make it happen no matter what and they could afford it. Simple as that
Let us wait for benchmarks before declaring anything.

We don’t need to, they have lost the power war already. I am not claiming that the XSX is better, but by numbers it is and will always be. You can not argue facts and numerical data.
 

Thirty7ven

Banned
I'm just going to leave this here and people can make what they want of it... A respected era insider, who also happens to be a mod there, left this nugget last night:


Here we go.

Like Clockwork.
 

PaintTinJr

Member
I'm just going to leave this here and people can make what they want of it... A respected era insider, who also happens to be a mod there, left this nugget last night:




"I'm not going to say too much, but from some murmurings I've been hearing, I'll just say I suspect this topic is going to age "interestingly" when a few more details on both platforms are revealed.

I mean this in a few more ways, but to give the broadest idea, I'll just say the Xbox X is by far more powerful than the PS5 if we're just talking raw power, multi-platform games will run better on Xbox X is something people are going to have to prepare themselves for. Add to this Microsoft are ready to lowball Sony when it comes to price. They can more easily make a sacrifice and get back profits from Game Pass than console sales than Sony can from that comparatively."
How does that address your claim about RT on each? Or undermine the technical argument I made - for why I believe (IMHO) you will be wrong about RT on both systems?

Are you now pivoting your point to compare cross-gen (multiplats without RT) on XsX and PS5, now? It is fine if you are, I don't disagree with that assertion, because I expect most UE4 and Unity based engine games will run better on XsX than PS5 for 2years until third parties release games using next-gen engines.
 

Dee_Dee

Member
Yeah, but I think the PS5 CU workgroups will be bigger because of the cache scrubbers - as that surely requires some additional unit to liaise with the memory controller that brings data to and from the unified ram to the L2 cache, wouldn't you think?

Also - can't remember if it was in an AMD, DF, Cerny or UE5 demo deep dive video, interview, technical docs or tweets, I watched/read. or if I've imagined it :pie_thinking: - but I've got it in my head that the PS5 GPU has 3 levels of cache hierarchy (L0, L1 and L2) - and that it might be custom to the PS5 because of the scrubbers. IIRC an L0 cache has been added to avoid CU WGPs thrashing the L1 cache and being forced to wait when the shared L1 cache gets updated. IIRC the 3 tier system allows the L2 cache to be updated , the L1 caches to partially change as needed, and the L0 cache to be used, uninterrupted until data needs move to/from the L1 cache. Hopefully I haven't imagined that, and some else remembers the same thing.
Oh yea I never heard about the other stuff you mentioned 🤷‍♂️.
 

Ascend

Member
I suspect that it has to do with AMD's mediocre scaling with large amount of CUs with the GCN architecture. They assumed AMD would still have that problem down the line, so they opted for as high clocks as possible while being relatively narrow, to avoid the exponential increase in inefficiencies with larger CUs.

RDNA doesn't seem to have the same scaling issues, but we won't be sure until we see the 64/72/80CU GPUs.
 

MaulerX

Member
How does that address your claim about RT on each? Or undermine the technical argument I made - for why I believe (IMHO) you will be wrong about RT on both systems?

Are you now pivoting your point to compare cross-gen (multiplats without RT) on XsX and PS5, now? It is fine if you are, I don't disagree with that assertion, because I expect most UE4 and Unity based engine games will run better on XsX than PS5 for 2years until third parties release games using next-gen engines.


I'm not "pivoting" anything. I made a claim and you made yours. Now we sit and wait.
 

Kumomeme

Member
probably:

-sony throw more budget into SSD, less on gpu side.
-as explained by cerny higher clockspeed 36cu is equal to 48cu so 36 is 'cheaper' than 48cu plus with additional rasterization performance
-ps4 backward compability perhaps?
- based on this gen, its 'common' for console manufacturer use mid range gpu and itseems the gpu sony use is midrange but on other hand, MS going all out for stronger monster gpu 52cu which is probably something sony didnt expect?
-Cerny believe 36cu is enough
-there interview before where devs claim lesser cu mean easier work for devs...i dont know if we can count on that or not.
-Sony actually considering Pro version from beginning so they do not worry for 'lesser specs' of ps5
-They know, in the end content matter not hardware
 
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llien

Member
52CU's vs 36CU's


This is a staggering difference when it comes to Ray-Tracing. It's an advantage that will be easily visible in multiplats games.
We don't know how RT is packaged at all, nor whether it will become an actual thing this gen.
 
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MrFunSocks

Banned
They've got a cost budget and a die size budget and they chose to put that money and space somewhere other than the CUs, nothing more. There's no magic in those CUs that MS don't have. AMD aren't in the business of screwing over one customer for another by hiding tech. Sony spent their money elsewhere (like the SSD), hoping that the higher clock speed can make up for a massive amount less CUs. I don't see it working, since variable clock speeds are worse in pretty much every way than constant clock speeds.

The XB1 had less CUs than the PS4 because of the eSRAM. While MS likely had the PR out going about how the eSRAM will make up for the CUs, or something else will, that's all it is - PR. Of course Cerny and Sony are going to say that their design is the best and gives them advantages and makes up for the lack of CUs, they're salesmen selling a product. It still baffles me to this day that people think Cerny has no vested interest and will only tell the honest to god truth so that means the PS5 is the more powerful console.
 

fybyfyby

Member
1: RDNA 2 is not a paradigm shift from RDNA 1, it is an evolution of it. this means they are very comparable.
2: current gen consoles compare to their respective PC parts pretty much 1 to 1 even tho they are modified. only a slight performance increase due to console optimizations are noticeable really. and as engines become more and more optimised for cross platform devlelopment we will see a reduction of these optimization benefits
3: so you had 2 PCs, one of them using a narrower GPU and one using a wider GPU clocked at the exact speeds so both would have the same theoretical teraflop performance? I don't know why I doubt that you did...



it is... to a point, at least with 360 games. we don't know with Xbox One games, an I would expect them to simply run natively with the API dong most of the heavy lifting when it comes to running the code.
also the Xbox One had hardware support for 360 software to a degree, meaning this was actually planned before the system launched, at least to some degree. so it is not full Software emulation there either.

not sure why you needed to point it out either way tbh. in the end the end user shouldn't really care how it works just how the end result turns out. which we will have to wait and see on both.
I think with 360games XOX/XSX is using CPU emulation in the first place. And rest is about graphics API, which I assume is not a problem for MS.
 

fybyfyby

Member
Let's be honest, you are going to sell what you have. I take that with a grain of salt, and the tests have shown better performance with more CUs and lower clocks.

I am actually looking for other reasons. Like if they stick with the same amount of Cu's, is there a benefit to their tools and engines?
Are Sony engines built around their GPU CU number, and so keeping the same amount means less work on that?

Or was it totally BC?
Maybe there is other possibility, why Sony has "only" 36 CUs. Remember fan arguing wether PS5 has RDNA1 or 2? And Mark Cerny said, that they closely cooperated with AMD to make custom chip and if some features of it will be available also on desktop, it will be success?

What if:
1)Sony develops custom RDNA1 chip with lot of new features - but with limitation of 40CUs
2)AMD uses some of these features for RDNA2, where there isnt this low CU limit
3)MS takes shelf RDNA2 for themselves

What if.... But that would make sense.

Its similar like with cell cpu. Sony developed it with IBM with one main core and seven utility cores. MS went to IBM and they sold them cell with 3 main cores. So it seems Sony always try to develop own designs and MS takes what is available.
 

Azurro

Banned
Maybe there is other possibility, why Sony has "only" 36 CUs. Remember fan arguing wether PS5 has RDNA1 or 2? And Mark Cerny said, that they closely cooperated with AMD to make custom chip and if some features of it will be available also on desktop, it will be success?

What if:
1)Sony develops custom RDNA1 chip with lot of new features - but with limitation of 40CUs
2)AMD uses some of these features for RDNA2, where there isnt this low CU limit
3)MS takes shelf RDNA2 for themselves

What if.... But that would make sense.

Its similar like with cell cpu. Sony developed it with IBM with one main core and seven utility cores. MS went to IBM and they sold them cell with 3 main cores. So it seems Sony always try to develop own designs and MS takes what is available.

These FUD attempts keep getting more and more stupid. At least put effort into the conspiracy theory.
 

BootsLoader

Banned
I never they would, they can if they want is the truth. They are one of the richest companies in the world. If they really wanted to they could undercut Sony 150$ Per console and be just fine. Not that they will, but they could. People seem to forget that Sony is not like MS when it comes to money. If MS wanted to really sell these consoles they will make it happen no matter what and they could afford it. Simple as that
No, because they have money does not mean they can undercut Sony 150$. The can’t do this even if they want it. It’s a huge loss and the XBOX division will close. You have to understand the economics behind companies. It’s more complicated than we think. Also you can’t just sell more because you are cheaper. You have to provide value. Microsoft wants to, but can’t for now.
 

Elog

Member
I'm not "pivoting" anything. I made a claim and you made yours. Now we sit and wait.

You repost a reply from era that got retracted by the author a few pages later as well as on twitter - and you repost that reply here when all of the retraction and backtracking was known without that added information. That is just sad.
 

ZywyPL

Banned
Probably because of:

A) BC, the obvious one.
B) cost savings - bare in mind there's a lot of custom stuff build around the SSD in the APU, which going by Cerny's slides take up half of the die space, so they had no other place to save on the transistors other than CUs.
 

PaintTinJr

Member
I'm not "pivoting" anything. I made a claim and you made yours. Now we sit and wait.
That's disappointing, I was hoping - like Cerny's Road to PS5 - you were going to dispel some prior thoughts I had about hardware.

FYI the first paragraph of: Expected behaviour/Terms of service strongly suggest that substantiation is expected here on Neogaf. God knows what the rules are on resetera - I've only been here, since early in the year and am not familiar with the other place ?
 

llien

Member
PS4 has essentially 7870.
This card has been released back in 2012 for MSRP of $269. (212m2 die size)
PS4 was released in 2014.

PS5 has a GPU that is faster than 5700XT, which was released in summer 2019 for $399. (about 250mm2 die size on a vastly superior process)
It is faster than 95% of what steam users are using (per steam hardware survey)

Why would they go with even bigger/faster chip, based on the previous history?
Microsoft's 56CUs are crazy.
 

PaintTinJr

Member
Maybe there is other possibility, why Sony has "only" 36 CUs. Remember fan arguing wether PS5 has RDNA1 or 2? And Mark Cerny said, that they closely cooperated with AMD to make custom chip and if some features of it will be available also on desktop, it will be success?

What if:
1)Sony develops custom RDNA1 chip with lot of new features - but with limitation of 40CUs
2)AMD uses some of these features for RDNA2, where there isnt this low CU limit
3)MS takes shelf RDNA2 for themselves

What if.... But that would make sense.

Its similar like with cell cpu. Sony developed it with IBM with one main core and seven utility cores. MS went to IBM and they sold them cell with 3 main cores. So it seems Sony always try to develop own designs and MS takes what is available.
The bolded part is completely wrong. The Cell BE is a HSA chip - the first ever - the "H" stands for "Heterogeneous" in Heterogeneous System Architecture. The Xenon chip was scaled down AS400 technology like the PowerMac 4 (IIRC) and is a "Homogeneous" chip like standard intel multi core
 

M1chl

Currently Gif and Meme Champion
The bolded part is completely wrong. The Cell BE is a HSA chip - the first ever - the "H" stands for "Heterogeneous" in Heterogeneous System Architecture. The Xenon chip was scaled down AS400 technology like the PowerMac 4 (IIRC) and is a "Homogeneous" chip like standard intel multi core
Except is correct, the main controller PPE core of PS3 got tripled in X360 cpu. It did not have SPEs.

Here is book about the whole ordeal at IBM https://www.amazon.com/dp/0806531010/?tag=neogaf0e-20

A on the wiki:
These cores are slightly modified versions of the PPE in the Cell processor used on the PlayStation 3.
 

fybyfyby

Member
The bolded part is completely wrong. The Cell BE is a HSA chip - the first ever - the "H" stands for "Heterogeneous" in Heterogeneous System Architecture. The Xenon chip was scaled down AS400 technology like the PowerMac 4 (IIRC) and is a "Homogeneous" chip like standard intel multi core
Yeah its homogenous because it has 3 main cores. I wrote it.

And read this:

Theres ton of articles about it. If you want to know it.
 
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MrFunSocks

Banned
Probably because of:

A) BC, the obvious one.
B) cost savings - bare in mind there's a lot of custom stuff build around the SSD in the APU, which going by Cerny's slides take up half of the die space, so they had no other place to save on the transistors other than CUs.
BC doesn't require the same hardware. Look at the 360 BC on the XB1. The XSX doesn't have 12 or 24 CUs just so it can have BC with the XB1.

B is the answer. They have a budget in size and cost, and their SSD and other things required for it blew out that budget, so they had to scale back the GPU and try to compensate for it with higher clock speeds.

Except is correct, the main controller PPE core of PS3 got tripled in X360 cpu. It did not have SPEs.

Here is book about the whole ordeal at IBM https://www.amazon.com/dp/0806531010/?tag=neogaf0e-20

A on the wiki:
These cores are slightly modified versions of the PPE in the Cell processor used on the PlayStation 3.
Lots of the team blue diehards don't understand that the main core of the Cell is basically the same as a single core in the 360 because they think the cell was some amazing witchcraft. IBM used the same knowledge to build both. The Cell is a fantastic number cruncher, but it should never have been used for gaming. It was one of the biggest swing and a miss's of the tech world in history tbh. Sony wanted it to be used in *everything*, from your mobile phone to your fridge to your tv to your game console. It was only ever used in a single device, and it was the reason why that device lost them billions of dollars.
 
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fybyfyby

Member
These FUD attempts keep getting more and more stupid. At least put effort into the conspiracy theory.
Why? These things happen. For example that cell cpu. What about it is stupid?

We dont know what happens between AMD, Sony and MS. Its wild guess of course. But according what happened in past (CELL CPU), these type of practices happens.

Someone takes shelf parts, someone co-develop own ones.

I dont know how it was, but this make sense primarily for number of CUs and speculations about PS5 having RDNA1+ GPU.
 

psorcerer

Banned
Why? These things happen. For example that cell cpu. What about it is stupid?

We dont know what happens between AMD, Sony and MS. Its wild guess of course. But according what happened in past (CELL CPU), these type of practices happens.

Someone takes shelf parts, someone co-develop own ones.

I dont know how it was, but this make sense primarily for number of CUs and speculations about PS5 having RDNA1+ GPU.

If it's "rdna1" but with features of rdna2 and on rdna2 tech process - it is rdna2
 

PaintTinJr

Member
Yeah its homogenous because it has 3 main cores. I wrote it.

And read this:

Theres ton of articles about it. If you want to know it.
You said they "sold them a Cell", that's the part that I am asserting is false and wrong. a CPU with three 2-way PPC Cores is not a Cell BE in any shape or form. The Xenon isn't a HSA chip, which is the fundamental part of that made a Cell processor a "Cell"
 

fybyfyby

Member
You said they "sold them a Cell", that's the part that I am asserting is false and wrong. a CPU with three 2-way PPC Cores is not a Cell BE in any shape or form. The Xenon isn't a HSA chip, which is the fundamental part of that made a Cell processor a "Cell"
I wrote they sold them cell with 3 main cores. What is contrdictive in this. Maybe I could write "cell with ONLY 3 main cores" to be perfectly acurate. If that is what was misleading, Im sorry for that.
 
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