Notice what Mark Cerny said?
he is saying that the second custom chip has a CPU in it so maybe that's the ARM CPU inside of the GNB.
'Graphic North Bridge' PlayStation 4's Custom Chip?
- Thread starter onQ
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Notice what Mark Cerny said?
he is saying that the second custom chip has a CPU in it so maybe that's the ARM CPU inside of the GNB.
No. The GNB is part of the apu. The 320 shader part sweetavar mentioned was probably just the apu from the early devkits.
NO. You've been told half a dozen times already, the GNB is a part of the APU. It lives on the same chip as the 8 Jaguars and the 18 CUs. Actually, the 18 CU actually belong to the GBN. It is NOT the second custom chip, nor is it on any second chip. There is a second chip, but that has nothing whatsoever to do with the GNB.
That much is certain, based on the terminology AMD has used on their previous products.
Sheesh.
OnQ, people would be much more willing to entertain and discuss your ideas (they are not totally crackpot, unlike some others here), if you actually read the posts that reply to you. We know what the GNB is, and it is not, in any way, related to a second custom chip.
I get that part, it just seems to me that the GNB in the PS4 is what Sony is calling the second custom chip.
like they actually put an APU & GPU together for the PS4 but used the CU's of the GNB from the APU as part of the secondary chip & it's what VGleaks & Eurogamer seen.
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Well, there's no evidence of that, and no reason to believe it.
How is it no evidence when Eurogamers said that it was a bespoke GPU-like compute module Paired up with the CPU with some resources reserved by the OS & VGleaks said that it was 4 additional CUs (410 Gflops) “extra” ALU as resource for compute?
Because there are dramatically more plausible explanations for those confused rumors then the bizarre, technically impossible "solution" you posit.
In a recent interview Cerny admitted, the PS4 would use ARM Trustzone. If this line of thinking is true, and there is an embedded ARM CPU in the southbridge for I/o, the it has to have it own memory. Very little will do, but it it's interesting what choice of SoC they go with.
Like what? & what's so impossible about the GNB of the PS4 APU being custom made to handle the OS features?
There are several pieces of evidence, some more accurate than others. Looked at as a whole, there are clear explanations that fit all the pieces far more comfortably than other explanations.
Explanation 1) the 14+4 rumour was true. Sony have chopped up the APU and put some graphics elements, 4 CUs, on the southbridge where there's an ARM CPU, conflicting with the official reveal that talked of 18 CUs in the GPU. So maybe the GPU has been upgraded and we have 18 CUs on Liverpool and the 4 additional CUs on the southbridge as part of the graphics northbridge
??? adding gigaflops computation that no-one has mentioned.Explanation 2 ) the 14+4 rumour was incorrect. Sony have installed a standard Fusion-type processor with 8 x86 cores and 18 CUs. The CUs constitute the Graphics North Bridge as is AMD's convention. There's a second low-power processor for background downloading and the like installed on the southbridge. Total CUs in the system is 18, all stationed in the Liverpool chip, all closely associated with the x86 cores via specific buses to facilitate communication between parts.
The only issue with the second explanation is where the 14+4 rumour fits in. That can easily be explained as a misunderstanding by its originator, or a limitation of beta hardware perhaps using two APUs (??). As the 14+4 rumour predates the official reveal, it is trumped in information by Sony's official information - and Sony have told us (in contrast to the other secretive console companies!) that their new console has 8 x86 CPU cores and 18 CUs with a peak 1.8 TF processing. As such, there's no confusion regards the architecture of PS4 unless one is unwilling to believe Sony's official press releases.
There are several pieces of evidence, some more accurate than others. Looked at as a whole, there are clear explanations that fit all the pieces far more comfortably than other explanations.
Explanation 1) the 14+4 rumour was true. Sony have chopped up the APU and put some graphics elements, 4 CUs, on the southbridge where there's an ARM CPU, conflicting with the official reveal that talked of 18 CUs in the GPU. So maybe the GPU has been upgraded and we have 18 CUs on Liverpool and the 4 additional CUs on the southbridge as part of the graphics northbridge
Explanation 2 ) the 14+4 rumour was incorrect. Sony have installed a standard Fusion-type processor with 8 x86 cores and 18 CUs. The CUs constitute the Graphics North Bridge as is AMD's convention. There's a second low-power processor for background downloading and the like installed on the southbridge. Total CUs in the system is 18, all stationed in the Liverpool chip, all closely associated with the x86 cores via specific buses to facilitate communication between parts.
The only issue with the second explanation is where the 14+4 rumour fits in. That can easily be explained as a misunderstanding by its originator, or a limitation of beta hardware perhaps using two APUs (??). As the 14+4 rumour predates the official reveal, it is trumped in information by Sony's official information - and Sony have told us (in contrast to the other secretive console companies!) that their new console has 8 x86 CPU cores and 18 CUs with a peak 1.8 TF processing. As such, there's no confusion regards the architecture of PS4 unless one is unwilling to believe Sony's official press releases.
Maybe they didn't mention the specs of the 2nd chip because it's for the OS & will be used for things like Remote Play , Video Chat , Web Browser , Video Recording & Uploading, PlayStation4Eye, Controller & Head tracking , Face Recognition & so on without effecting the Gameplay.
Example: Remote Play has been said to be hardware based & can run at anytime without using any of the CPU or Ram with the game playing on your TV & the PlayStation Vita at the same time.
Where does that theory fit in with Sony's pretty open communication. We're told there's a second CPU for downloading stuff in low-power mode. Why no mention of the third OS CPU, or dedicated silicon to ensure Os tasks don't interrupt your game experience? You're suggesting a considerable investment by Sony that they are then not marketing as added value in their system, which makes zero commercial sense. If there was 400 GF of processing for PSEye, video chat, web browser, face recognition etc., they'd have said as much, no?
As for things like remote play being hardware based, you just need a hardware h.264 encoder for that. That's a hardware feature of the GPU that can be used for any video streaming functions. For things like controller tracking, what do you expect the CPU to be doing?
As for things like remote play being hardware based, you just need a hardware h.264 encoder for that. That's a hardware feature of the GPU that can be used for any video streaming functions. For things like controller tracking, what do you expect the CPU to be doing?
The Guy who 1st leaked the info about the PS4 switching to a Jaguar CPU back in April of last year. this was even before VGleaks posted about the PS4 having a Steamroller CPU in June of last year so he was ahead of them & his info was more up to date.
http://www.vgleaks.com/world-exclusive-ps4-in-deep-first-specs/
The original post are deleted now to protect his roommate who works at AMD.
http://forum.beyond3d.com/showpost.php?p=1640144&postcount=11460
Full post http://neogaf.com/forum/showpost.php?p=40411509&postcount=630
Where does that theory fit in with Sony's pretty open communication. We're told there's a second CPU for downloading stuff in low-power mode. Why no mention of the third OS CPU, or dedicated silicon to ensure Os tasks don't interrupt your game experience? You're suggesting a considerable investment by Sony that they are then not marketing as added value in their system, which makes zero commercial sense. If there was 400 GF of processing for PSEye, video chat, web browser, face recognition etc., they'd have said as much, no?
As for things like remote play being hardware based, you just need a hardware h.264 encoder for that. That's a hardware feature of the GPU that can be used for any video streaming functions. For things like controller tracking, what do you expect the CPU to be doing?
They never said that the 2nd Chip was a CPU Mark Cerny said that the chip had an embedded CPU in it.
Also if you watch the PlayStation Meeting again when he is talking about the Social part of the PS4 he says that it's custom hardware for it.
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The chip is the southbridge. It'll have lots of controllers as well as the CPU. That doesn't mean it includes CUs, or even hints at it having CUs.
Yes, which only needs a video encoder custom hardware.
How's about you answer one of my questions directly? I ask you, if PS4 has significantly more computational resources than the 8x CPU cores plus 1.8 TF 18 CUs that Sony have explicitly told us about, why are they not communicating that extra performance?
It could be included in the 1.84TFLOPS as the 4CU's that's added to the 14CU's leaving 1 CU reserved for the OS.
that would make sense of VGleaks , Eurogamer & the 5 SIMD 320ALU's from the Starsha GNB.
Eurogamer : GPU-like Compute module, some resources reserved by the OS
= 1 of the 5 CU's of the GNB reserved for the OS with the other 4 as part of the GPU.
VGleaks: About 14 + 4 balance:
- 4 additional CUs (410 Gflops) “extra” ALU as resource for compute
- Minor boost if used for rendering
= 4 of the 5 CU's from the GNB added to the 14CU's of the GPU as part of the GPU & the 5th CU/ALU is resource for compute but can be used for a minor boost in rendering.
Sweetvar26's Starsha GNB: SIMD’s 5 , Scalar ALU’s 320
= 5 CU's with 4 as part of the GPU & 1 being used for Background Processing /OS.
But not make sense with Sony's official press release of an 18 CU 1.8 TF GPU.
I also don't understand why you'd reserve 1 CU for the OS. A CU is not like a CPU and has limited applications. The design of the APU is about farming off select jobs onto the GPU which it'll be good at, and using the CPU for everything else.
Found the original Starsha rumour. That source was talking about Durango being a supercomputer, and both platforms being a single chip solution, and the APU being called Starsha even though we know it's Liverpool. He never mentions two APUs. I have no idea why you're placing so much emphasis on it, especially over the official specs from Sony. Or even the Edge rumours that told us about 8 GBs GDDR5 and touch-pad controller and Liverpool SOC.
You're suggesting that in reality that GPU is divided in two across two chips, Liverpool and southbridge.
I also don't understand why you'd reserve 1 CU for the OS. A CU is not like a CPU and has limited applications. The design of the APU is about farming off select jobs onto the GPU which it'll be good at, and using the CPU for everything else.
Found the original Starsha rumour. That source was talking about Durango being a supercomputer, and both platforms being a single chip solution, and the APU being called Starsha even though we know it's Liverpool. He never mentions two APUs. I have no idea why you're placing so much emphasis on it, especially over the official specs from Sony. Or even the Edge rumours that told us about 8 GBs GDDR5 and touch-pad controller and Liverpool SOC.
First thing first, sweetvar's info may have been misinterpreted. He said 5 SIMDs. Not 5 CUs. In GCN terms, 1 CU has 4 SIMDs. This Starsha thinggie has 5 SIMDs ("just" 1 extended CU ?). There is no 410 GFLOPs here if that number is calculated from 4 CUs.
The 14+4 CUs rumor still matches Cerny's 18 unified CUs announcement. 18 is aplenty. They run assorted compute jobs together, compared to fixed partitioning implied by 14+4.
Now back to Starsha...
RemotePlay, video and audio stuff makes use of the video and audio decoders. The AMD CPU can switch to run the web browser easily.
Head tracking, voice recognition, ... can be run by the Jaguar vector engines or the GPU's CUs.
I suppose the ARM CPU could also have a vector engine to handle security operations, but I don't think they need 410GFLOPs for it.
If we prune the rumors based on the apps we know so far, there is little need for an additional compute unit. It would be extra programming hurdle to use Starsha (why not SPUs ?). They want simplicity.
I did notice that according to Cerny's interview, the secondary chip is there partly for energy efficiency. So perhaps Jeff Rigby has partial credits.
If we believe in every single rumor, it will be like playing Demon's Souls. Every time we have to restart the thread albeit capped at half the patience and sanity. It's probably best to keep Starsha aside and wait for more info. Sweetvar's tip may have been too early (i.e., killed) as one of the posters pointed out.
The 14+4 CUs rumor still matches Cerny's 18 unified CUs announcement. 18 is aplenty. They run assorted compute jobs together, compared to fixed partitioning implied by 14+4.
Now back to Starsha...
RemotePlay, video and audio stuff makes use of the video and audio decoders. The AMD CPU can switch to run the web browser easily.
Head tracking, voice recognition, ... can be run by the Jaguar vector engines or the GPU's CUs.
I suppose the ARM CPU could also have a vector engine to handle security operations, but I don't think they need 410GFLOPs for it.
If we prune the rumors based on the apps we know so far, there is little need for an additional compute unit. It would be extra programming hurdle to use Starsha (why not SPUs ?). They want simplicity.
I did notice that according to Cerny's interview, the secondary chip is there partly for energy efficiency. So perhaps Jeff Rigby has partial credits.
If we believe in every single rumor, it will be like playing Demon's Souls. Every time we have to restart the thread albeit capped at half the patience and sanity. It's probably best to keep Starsha aside and wait for more info. Sweetvar's tip may have been too early (i.e., killed) as one of the posters pointed out.
He never called Starsha an APU when he posted the info about Starsha he said: "New Starsha GNB 28nm TSMC"
& where are you getting 2 APU's from?
I'm saying CPU + Starsha GNB + GPU = PS4 custom APU.
If anything GNB sounds like an updated version of the Wii U's GPU die, that's probably just a coincidence though.
If you are basing your information on the Indeed.com CV, isn't the line stating "GNB is targeted for 20nm technological library with GF foundaries" enough to rule it out for any of the upcoming consoles?
If you are basing your information on the Indeed.com CV, isn't the line stating "GNB is targeted for 20nm technological library with GF foundaries" enough to rule it out for any of the upcoming consoles?