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Wii U CPU |Espresso| Die Photo - Courtesy of Chipworks
- Thread starter Fourth Storm
- Start date
bgassassin
Member
I suck at drawing and can't even consistently draw straight lines with a tool, but I made a couple of approximations of the cores.
Yeah, the GPU thread brought me back and since they said the CPU was coming I waited.
Ok. Glad you found that much.
I didn't know the formula, but I did feel it was supposed to be smaller than LiB's calculation. I've seen it where just transitioning to the next node has reduced size by like 30%.
Yeah, the GPU thread brought me back and since they said the CPU was coming I waited.
Ok. Glad you found that much.
I didn't know the formula, but I did feel it was supposed to be smaller than LiB's calculation. I've seen it where just transitioning to the next node has reduced size by like 30%.
lostinblue
Banned
Could be, I thought about it before writing. But... I don't think so.
My reasoning was that Broadway (90 nm) is also manufactured at half of Gekko's 180 nm process and it sits at roughly half the die area instead of a fourth. But... it's also less than half by 2 mm² or so and seems to have added things (and the size proportion of the cache banks changed in there)
I was probably oversimplifying it, but if anyone knows how to go about it please do. All in all though, it feels fishy, if each of those dies are the equivalent of a Gekko/Broadway (or even just the middle one), feature 4 times the cache and have that left sided block thing going on, I reckon it's kinda small.
TheLastCandle
Member
I see, said the blind man.
bgassassin
Member
I think you can see that they're three of the same a bit better if you separate out the cache.
I believe those are the SRAM tags as wsippel said, that said I like yours better.
Mentallyerect
Neo Member
Lurker here, love what you guys have been doing with the GPU thread and now this (even though must of this is over my head) Quick question though. Once those of you who are breaking these images down get the best hypothesis on what both the GPU and CPU are, will you create another thread detailing both and how the possibly coexist and work off each other to their benefit?
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
Or not. The area calculation does not come right for those to account for the L2.
lostinblue
Banned
Oh, never thought about them as L2 tags. Might be; never mind what I said regarding expected die size; I was counting that left block as something other than cache.
lwilliams3
Member
The GPU is likely 40nm. The CPU is confirmed to be 45nm.
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
Nope - 45 vs 40 (and different fabs - IBM vs TSMC).
I'm currently of the opinion the black area on the left are the eDRAM macros, the areas you marked in magenta are indeed tags (SRAM), and the logic in between the L2 and the cores is SMP interconnect fabric. The 9 SRAM pools in the top-middle are some sizeable of IO buffers - perhaps for the DMA engines.
bgassassin
Member
Those being the L2 tags do make the most sense, because the black blocks seem the be the L2 cache. Like I mentioned I calculated each of those blocks to be 256KB.
I see you're saying they are the tags now, haha.
CPU is 45nm. But yeah the L2 cache has to be the black blocks.
Probably depends on perspective. When the poster Espresso talked about it on B3D he focused on the the few features given that came from Gekko/Broadway. However that line could not be clocked at Espresso's current clock and I don't believe they could support the amount of cache that the main core does as well. IMO I would say it definitely is not a straight up Gekko/Broadway. But there were things done for BC purposes.
lostinblue
Banned
It's most likely still PPC 750 based though otherwise they couldn't keep code compatibility locked down.
I'm way more curious if they added things to it; more SIMD instructions (like VMX128) or enhanced integer. But I'm not counting on it.
lostinblue
Banned
With a core shrink this agressive, it most likely could. I mean you had PowerPC 750GX pulling 1.1 GHz @ 130 nm's.
1.24 GHz is a small step considering it's 45 nm's now, and probably down to MHz/Watt consumption sweet spot and cooling concerns.
this is something many people know from wii age... it cant be wii cores.. because the tech of wii core, was not able to come in a multi core chip... and it couldnt come in higher clocks.. its something different
Naked Snake
Member
Only three Wii cores? Sounds weaksauce
I guess Dolphin emulation of Wii U is eminent?
I guess Dolphin emulation of Wii U is eminent?
bgassassin
Member
Based on it I can see.
Orionas mentioned the VX, which I didn't know about, and that did achieve higher speeds.
You only took a portion of that post. Apparently his evidence was based on the limited features given in the docs. Looks at the features he gave in that post and then look at what was leaked by VGLeaks.
http://www.vgleaks.com/world-premiere-wii-u-specs/
I think you can see that they're three of the same a bit better if you separate out the cache tags.
The areas above the L1 that you have as gaps between the cores are actually part of the core logic, as far as I can tell. My current theory is that this is where the LSU resides in each core.
Some of it's cache logic, the rest is for communication between the cores.
lostinblue
Banned
Did it? I didn't know about it either but sounds like an urban myth and even if it wasn't it never reached production.
PowerPC G3+Altivec and "probably" 1.25 GHz and up? It's not listed or documented by IBM to this day too. I'm sure it could be done but I'm not so sure it was done; even posts from the time in that thread question it's existence.
VX seems like old rumors/conjecture that never came to fruition, PPC750 CL was released as late as 2006; VX never did. I agree it could be a best case scenario for this chip, but I doubt it.
Only if you're emulating Wii U emulating a Wii game.
bgassassin
Member
Yeah. As I searched further it seemed to be on paper only.
I transfered the opinion of a wii U member.. its not mine, but he also said that the cpu was ready for Apple, but apple abandoned this and alianced with Intel and created the "i core"
so here is the message I hope this guy helps, he is specwise, I am sure he is reading also here
'''These look to be 3 (custom) ppc750 fx's, and the fat boy in the middle is a little wierd, its the same size as the fx's, but it appears to have a few extra logic components.... And twice the cache of the 750Gx (but it if it was a gx, it would be noticably larger than its buddies above and below... which its not.)
These are all code compatable with every processor in the 750 family, including 750Cx (Gekko) 750cle (broadway) (and any and all g3 computers/ibooks/laptops)
A little info about the difference between 750fx and cle.
Fx has about twice the transistor count of cle, and smokes in instructions per clock and performance per watt.... And it has never, EVER been fabricated this small or clocked this high.... or made multicore.
It would be epically hilarious if this ended up being a derivitive of the mythical 750vx. IBM was planning a ppc750 to replace the disasterous 64bit ppc 970 (g4's/g5's, what would eventually be the basis of both xenon and cell)
It was the ppc750Vx, and at 2Ghz, a vertex engine and just 1 core, it could handidly outperform tricore g4's clocked considerably higher... Which would have placed it paralell to the g5 as a replacement to the g4.
Vx never saw the light of day because apple ended their partnership with ibm over the piss poor performance of the 970, and forged a an alliance with intel, creating the icore. ''''''
tkscz
Member
No. While both are in the same CPU family, the WiiU uses the 750FX (or something close to the Fx and Gx) and the Wii use 750cle. Think of it like intel sandy bridge and Ivy bridge, same family, but not the same things.
Note: I'm using that example as a reference point, not a power comparison.
The person who originally made that claim noticed (probably on paper) that they were both in the PPC 750 family, and didn't bother trying to find out which place in the family it was in. Instead, just assumed it was a tri-core PPC 750cle, which, as previously stated by Orionas, isn't possible.
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
Ahem.
970 was anything but 'poor performance', let alone 'piss poor', and replacing that with a 750, no matter how advanced, would be out of the question. Apple terminated their IBM (and Moto) partnerships for two very simple reasons, none of which was 'piss poor performance' of any of the chips they used during that time:
1. Both IBM and Moto (IBM more so) underperformed WRT their roadmaps - often time a new clock / speed bump was expected, that occurred with a considerable delay, if ever. That's what happened to many G3 (IBM), G4 (Moto), and eventually G5 (IBM 970) chips. That messed up Apple's own roadmaps - they often promised a certain clocked model, which they had to downclock come launch, or postpone altogether.
2. Apple effectively constituted the entire mass market for high-performance PPCs - G3 and above (G2 staying healthy the embedded/automotive). That makes for a very bad economy of scale.
Re the FX and GX - those are _not_ code-compatible with every G3 ppc ever - the Gekko extensions are found _only_ in the CL. You don't have to take my word for it - read IBM's own publicly-available documentation.
As re the basis of Xenon/PPE - that most definitely was not the 970 AKA G5.
lwilliams3
Member
Can someone make a size comparison of Espresso vs Broadway and Gekko if it was on the same process? The broadway vs Latte photo posted at the GPU thread opened some eyes.
frankie_baby
Member
that would certainly be useful
Typically chips that have hand laid transistors by humans look more computer-ish with straight symmetrical lines, and more mushy looking stuff like this was laid out by auto layout computer programs. See the Apple A6 die which was hand tuned, the CPU parts are very clean looking, the GPU and uncore parts are computer layed and so more mushy looking.
Funny, that something designed by computers would look more organic than something designed by humans.
Also this is what I was talking about in my prior post, Chipworks also got the A6 die for us, how come it looks so much sharper than the Espresso die?
Also what are the big squares to the left?
phosphor112
Banned
Nice, awesome of them to throw this in as well. Not as exciting as the GPU shot, but still cool regardless.
frankie_baby
Member
broadway was out of order in the first place
Really? I was completely unaware of that. The way people talked made it seem like a just a copy and paste of Gekko with a 50% higher clock and nothing more.
I'm pretty sure Gekko was an OOO CPU as well.
ColdBlooder
Banned
Is it me or is Core 1 (With the 2mb cache) significantly dfferent than the 2 cores with 512kb? (Those 2 cores are identical to me).
And no im not taking cache size.
Whats different about Core 1 than Core0 and Core 2 except the cache size?
And no im not taking cache size.
Whats different about Core 1 than Core0 and Core 2 except the cache size?
tkscz
Member
Regardless, broadway couldn't be "cored" nor could it reach Espressos clock speeds. They are both PPC 750 based, but not the same PPC 750.
frankie_baby
Member
as already stated gecko was OOO too, also the die shots seem to suggest (imo) there may have been at least slightly more to broadway annyway
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
IIRC late ppc750, Gekko/Broadway included, are not exactly in-order - they have limited out-of-order capabilities. The op decoder stage decoded up to 4 ops per clock, and places them on a queue. The dispatch unit picks among the front 2 ops of the queue (with dependency & branch resolve), and dispatches up to 2 ops, plus the branch resolve, i.e. 2 ops + branch is the max dispatch rate. So the ops travel the pipelines in order (and are retired in order), but their dispatch can be out-of-order, in a very small window. One can think of it as a very short out-of-order design.