AMD: ZEN3 architecture finished – expects 15% faster IPC





AMD’s earlier this week hosted a presentation at the SC19 conference, an International Conference for High-Performance Computing, Networking, Storage, and Analysis. AMD made some interesting remarks about ZEN3 and Epyc in regards to development as well as IPC increases.
First off, AMD mentions the ZEN3 architecture design phase has been finished. Nowadays you can look at AMDs design and release phases as the traditional tick-tock release schedule. Here you may expect an iterated update of ZEN2. That’s said, ZEN3 should be seen as a new architecture is mentioned, which is interesting. We know that ZEN3 is a 7nm+ based product based on the below roadmap slide that was shared a while ago.
Zen1 compared to Zen2 brought a clock-for clock IPC increase of 21%, AMD says it careful, but hints at yet another 15% IPC increase for ZEN3, that’s again clock for clock and not counting faster clock frequencies. The necessity of more cores has not ended, and the future design path will be based on more cores and a greater compute density as well as a focus on memory bandwidth and I/O connectivity.
AMD qualified the remarks by pointing out that Zen 2 delivered a bigger IPC gain than what's normal for an evolutionary upgrade - AMD has said it's about 15% on average - since it implemented some ideas that AMD originally had for Zen but had to leave on the cutting board. However, he also asserted that Zen 3 will deliver performance gains "right in line with what you would expect from an entirely new architecture."
Despite earlier rumors, AMD also confirmed that ZEN3 and Epyc CPUs will not use a maximum of four threads per core, so you can 'bin' that idea. On the Epyc side, there was news as well, Amazon will be deploying Epyc 2 technology for their server farms and thus web services servers, which is huge for AMD of course. 64-core Rome processors will also be used in Microsoft's Azure service.
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They’ve redesigned the architecture for Zen 3. The cache will be very different and not have latency issues like Zen 2 because of CCX. The cache will be shared by all cores, so it won’t matter if Windows makes a single thread jump from core to core all over the CPU.
There might even be a L4 cache.
Lets hope they will lower the Latency and fix Core Scheduling performance loss which is present in Zen 2. CCX , because Windows can't use the cores to their max. potential with Zen 2 CPU's. Agree that big part of the improvements in IPC will come from the cache memory shared by all cores in Zen 3 for sure.
First we fix the CCX design errors from Zen 2 in Zen 3 ,after we speak about the 15 % improvements in IPC in Zen 3, clear win win situation
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I just wish they'd build a decent CPU/APU for laptops that doesn't hog battery like current ones do.
Intel basically has 100% of the laptop market (which is not a small market at all) and even nowadays it's still difficult to recommend anything with an AMD CPU/APU.
As for their desktop CPUs, I'm impressed by Zen 2/3... but if I had to buy anything, I'd probably wait for Zen 4, which will have 3 or 4 threads per core, and will probably bring DDR5 (couldn't care less about PCI-Express 5.0 though). If Zen 3 delivers, surely Zen 4 will be a complete beast.
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There's always going to be a latency penalty communicating BEWTWEEN CCX's. This is an inherent limitation of the design. You can some what mitigate via the evils such as branch prediction, you will not eliminate it.
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AMD has a year or two , before Intel closes the performance gap, therefore now is time for AMD to come up every year with the new CPU architecture and new CPU design. Intel has 14 nm matured vs 7 nm new process technology that AMD has, it is more than obvious who is a winner here for me
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I wish a Zen3 8core/16thread CPU would be compatible with my X370 motherboard.
Then again, if not, Zen 3 would probably mean that I'd be able to get my hands on a 3700X on a really good price sometime in the future.
That would bring a nice performance boost over my 1700.
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delete
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Might as well hold on to my 4770K for a little longer then.
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I'm holding on to my 5960X a little longer so I can get the Ryzen 4950X lol which will either be 16 cores or maybe even 20, but I doubt it. I'm basically looking to double my core count so I can have additional cores/threads for background tasks and very competitive gaming performance, though it will be at 4K, so it'll likely even out.
I'm still very impressed by the 3950X, but I don't have a real "need" for it yet. 8 cores and 16 threads is enough to game today, but it falls short in content creation.
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Yeah
I also think this "completely new architecture" thing people keep saying and AMD keeps like throwing around is kind of nonsense. It's not a completely new architecture. Zen 1 wasn't even a completely new architecture - a ton of stuff was pulled in from Bulldozer. I feel like the tech community needs to create some kind of benchmark on how much a design needs to change to be considered a "new architecture".
It's different enough for AMD to change processor family from 17h of Zen1/+/2 to 19h in Zen3. Granted, they've switched it once (or twice if you count going from CPU to APU) before on quite flimsy basis, but it's definitely not a habit
Then again, if not, Zen 3 would probably mean that I'd be able to get my hands on a 3700X on a really good price sometime in the future.
That would bring a nice performance boost over my 1700.
So long as they can fit everything in the BIOS (which has been a challenge as we know) there's no reason it wouldn't work. Zen4 will require new socket and motherboard though (and memories to accompany, DDR5)
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I am still holding onto overclocked 3770K, but it's finally turned into a major pain in the ass. Lightroom just doesn't work well it at all, freezing and being slow as hell all the time and I don't know if I can keep using this PC for much longer. Zen3 definitely looks like something to wait for, but we're looking at like 7 months from now at least. I just don't know.
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Where was the original estimate 8%?
I'm just saying - the article headline is "AMD expects 15%" but then in the actual article, the guy basically says "15% for Zen 2 was basically an outlier because there was left over optimizations - expect a normal jump for Zen 3" which reads to me like less than 15%, not 15%.
I doubt this is going to be a radical departure from Zen 2. It's not like a Bulldozer -> Zen jump.
Gee I just make things up ..….you got me!
https://www.kitguru.net/components/cpu/joao-silva/zen-3-could-see-ipc-gains-over-8-and-up-to-200mhz-faster-clocks/
https://www.notebookcheck.net/Intel-should-be-worried-again-AMD-Zen-3-IPC-gains-rumored-to-be-greater-than-8-with-up-to-200-MHz-increase-in-clocks-compared-to-Zen-2.438940.0.html
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Gee I just make things up according to you...….
https://www.notebookcheck.net/Intel-should-be-worried-again-AMD-Zen-3-IPC-gains-rumored-to-be-greater-than-8-with-up-to-200-MHz-increase-in-clocks-compared-to-Zen-2.438940.0.html
Yeah, I mean I was expecting an AMD estimate of 8% not a forum rumor. So now it's like forum rumor = 8% and then you're taking that rumor and saying it's easy to see how it could be 15%.
It's speculation on top of speculation and the only statement we have from AMD is essentially "the 15% from Zen 2 was due to optimizations being pushed from Zen+, expect more normal numbers from Zen 3"
Which to me means 4-6% IPC gain maybe 8 if you include the frequency bump.
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it appears to be a misquote.
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Zen 4 will be a new socket, probably AM5. Zen 3 will of course launch with a new chipset and motherboard.
DDR5 will arrive with Zen 4 in 2021 along with PCI-Express 5.0 and it’ll likely be 5nm from TSMC. I guess 5 is the magic number for 2021.
EDIT: Almost forgot the most important detail most have overlooked. Memory support. If Infinity Fabric is again faster than Zen 2, and maybe always 1:1 up to 4600... That'll have a big impact for performance. Right now with Zen 2...anything over 3733 drops the Infinity Fabric to 2:1.