PlayStation 4 (codename Orbis) technical hardware investigation (news and rumours)

Status
Not open for further replies.
All I can think is either; 4 CUs disabled for redundancy/ yields or 4 CUs dedicated for compute?

If it was there for redundancy/yields, then it wouldn't have been mentioned.

If it truly does only have the performance of 14 CUs, that makes it closer to Durango. But then as I mentioned in the other thread, why have 18 CUs if that is the case.

I can't imagine they can "lock" 4 CUs into compute only tasks, unless it was on another package. But I'm not sure sure that would even make sense.

Or perhaps they mean that it can only efficiently use 14 CUs and hence has the performance of 14 CUs. But considering you don't do that with GPUs in general on PC or otherwise (where efficiency is never close to 100%), that wouldn't make sense either.

Regards,
SB
 
From vgleaks comments by the author

Soon we will detail what is composing each CU and its 14+4 division.

Also, we will provide more info about the GPU and extra components listed in the article.

There's your special sauce :)

But the "14+4 division" smells like reserved CUs.
 
If it was there for redundancy/yields, then it wouldn't have been mentioned.

If it truly does only have the performance of 14 CUs, that makes it closer to Durango. But then as I mentioned in the other thread, why have 18 CUs if that is the case.

I can't imagine they can "lock" 4 CUs into compute only tasks, unless it was on another package. But I'm not sure sure that would even make sense.

Regards,
SB

Exactly, developers don't need to know about technical yield concerns. They just need to know what hardware they're being guaranteed.
 
There is the possibility that the rumor was wrong.

That too, which makes me wonder why Leadbetter was so adamant about it's inclusion in his article by using the terms 'secret sauce' and 'standalone inclusion.' In every part of his words he makes it sound like it is a fully unique processor in the system.

That's the only reason I was interested in this extra piece, because his article made it seem like it's inclusion was already packed in.

If he misinterpreted something completely and it came out in the article as that, who knows.
 
Even Leadbetter made clear that his rumored module makes little sense since you could accomplish the same thing by adding CUs to the GPU which could also be used for graphics

We're assured that this is bespoke hardware that is not a part of the main graphics pipeline but we remain rather mystified by its standalone inclusion, bearing in mind Compute functions could be run off the main graphics cores and that devs could have the option to utilise that power for additional graphical grunt, if they so chose.

so my guess would be that the rumor was always inaccurate (and probably referring to the 4 additional CUs)
 
It just doesn't make sense why he would say 'we're assured' then. It's implying there is some guarantee to it, and then he says 'well it doesn't really make sense.' What kind of assurance is that?

It seems to me he was playing with words and there is nothing extra in the end.
 
Even Leadbetter made clear that his rumored module makes little sense since you could accomplish the same thing by adding CUs to the GPU which could also be used for graphics



so my guess would be that the rumor was always inaccurate (and probably referring to the 4 additional CUs)

Yep, that's my guess too.

We still need to know what its benefits and limitations are.
 
Very true , but this must be first generation of home consoles that are this closely related.

For modern major consoles, this seems true.
Going back to early machines that played games at home, there were things like Atari clones and the like.

The challenges of the performance and design space consoles have pushed into and the economics of the industry right now mean that the cost for doing your own thing is massive.
The upside is also pretty limited, because the remaining players in this space have survived nearly a decade of brutal competition and expensive R&D. Their existing stuff is likely better than any clean-sheet design can hope to be, given how intractible the problems modern computing faces are.

So the chance that Durango and Orbis use extremely similar CPUs, that can't be coincidence, right?
They chose the same company, who had two choices to offer, and one choice was not looking too hot.
 
14+4 CUs could be related to the graphics context switching . when not gaming - only the 4 CUs would be running with cpu .

i think the liverpool gpu is designed as 18 CUs gpu . One exception is that the 14 CUs can be turned off when not needed or can be used as total 18 CUs for graphics if the developer choose to .
 
Wouldn't the number of FLOPS between D&O be closer if the CU count is this close?

Can somebody explain to me how these Compute Units work? I mean these are for graphic tasks right?

Are they like the streaming processors in conventional GPUs? If so, though, how does it work if there are only 18 or so CU's in this souped up APU yet there are literally hundreds of Stream Processors in conventional desktop GPU's?
 
Can somebody explain to me how these Compute Units work? I mean these are for graphic tasks right?
I would suggest reading up on AMD's GCN architecture.
A CU is mostly the equivalent of a core, but to try to describe it in depth is going to flood this thread.
A CU has four vector ALUs, and each lane in the vector units is what the marketers call stream processors, although they aren't processors at all.
 
I would suggest reading up on AMD's GCN architecture.
A CU is mostly the equivalent of a core, but to try to describe it in depth is going to flood this thread.
A CU has four vector ALUs, and each lane in the vector units is what the marketers call stream processors, although they aren't processors at all.

Reading on it. Read something about basically Vector ALU's are what people would consider "stream processors" and there's something like 64 of them per CU, so the total "stream processor" count for the Orbis would be 1152. The HD 7970 has 32 CU's by comparison according to what I read.

It's just somewhat confusing given when reading up on GPU tech (like from Nvidia) they boast how many hundreds of stream processors are in their latest GPU and then when reading about Obis\Durango suddenly its "x Compute Units" not even breaking 50. It's a novice mentality, but at first blush it's hard to shake the "less = less powerful" reaction.
 
Can somebody explain to me how these Compute Units work? I mean these are for graphic tasks right?

Are they like the streaming processors in conventional GPUs? If so, though, how does it work if there are only 18 or so CU's in this souped up APU yet there are literally hundreds of Stream Processors in conventional desktop GPU's?

The CUs in AMD's GCN architecture correspond to groups of stream processors. If my math is correct, 18 CUs would contain 1,152 stream processors.

Edit - As you found yourself.
 
I appreciate the helpful input though Mr.Corbo. Had I waited just a few minutes you'd have brought me fully up to speed and saved me the trouble!

Much appreciated.
 
14+4 CUs could be related to the graphics context switching . when not gaming - only the 4 CUs would be running with cpu .

i think the liverpool gpu is designed as 18 CUs gpu . One exception is that the 14 CUs can be turned off when not needed or can be used as total 18 CUs for graphics if the developer choose to .

Hardware balanced at doesn´t sound exactly like that, I think.
 
Status
Not open for further replies.
Back
Top