AMD Zen 2 Microarchitecture Analysis: Ryzen 3000 and EPYC Rome
by Dr. Ian Cutress on June 10, 2019 7:22 PM EST- Posted in
- CPUs
- AMD
- Ryzen
- EPYC
- Infinity Fabric
- PCIe 4.0
- Zen 2
- Rome
- Ryzen 3000
- Ryzen 3rd Gen
Editor's Note: With Zen 2 set to launch tomorrow (7/7), here's our architecture analysis from last month for some timely background information.
We have been teased with AMD’s next generation processor products for over a year. The new chiplet design has been heralded as a significant breakthrough in driving performance and scalability, especially as it becomes increasingly difficult to create large silicon with high frequencies on smaller and smaller process nodes. AMD is expected to deploy its chiplet paradigm across its processor line, through Ryzen and EPYC, with those chiplets each having eight next-generation Zen 2 cores. Today AMD went into more detail about the Zen 2 core, providing justification for the +15% clock-for-clock performance increase over the previous generation that the company presented at Computex last week.
AMD’s Zen 2 Product Portfolio
The current products that AMD has announced that have Zen 2 cores include the Ryzen 3rd Generation consumer CPUs, known as the Ryzen 3000 family, and AMD’s next generation enterprise EPYC processor, known as Rome. As of today, AMD has announced explicit details of six consumer Ryzen 3000 processors, including core counts, frequencies, memory support, and power. Details about the server processor, aside from some peak values, are expected in due course over the next few months.
AMD 'Matisse' Ryzen 3000 Series CPUs | |||||||||||
AnandTech | Cores Threads |
Base Freq |
Boost Freq |
L2 Cache |
L3 Cache |
PCIe 4.0 |
DDR4 | TDP | Price (SEP) |
||
Ryzen 9 | 3950X | 16C | 32T | 3.5 | 4.7 | 8 MB | 64 MB | 16+4+4 | 3200 | 105W | $749 |
Ryzen 9 | 3900X | 12C | 24T | 3.8 | 4.6 | 6 MB | 64 MB | 16+4+4 | 3200 | 105W | $499 |
Ryzen 7 | 3800X | 8C | 16T | 3.9 | 4.5 | 4 MB | 32 MB | 16+4+4 | 3200 | 105W | $399 |
Ryzen 7 | 3700X | 8C | 16T | 3.6 | 4.4 | 4 MB | 32 MB | 16+4+4 | 3200 | 65W | $329 |
Ryzen 5 | 3600X | 6C | 12T | 3.8 | 4.4 | 3 MB | 32 MB | 16+4+4 | 3200 | 95W | $249 |
Ryzen 5 | 3600 | 6C | 12T | 3.6 | 4.2 | 3 MB | 32 MB | 16+4+4 | 3200 | 65W | $199 |
The Zen 2 design paradigm, compared to the first generation of Zen, has changed significantly. The new platform and core implementation is designed around small 8-core chiplets built on TSMC’s 7nm manufacturing process, and measure around 74-80 square millimeters. On these chiplets are two groups of four-cores arranged in a ‘core complex’, or CCX, which contains those four cores and a set of L3 cache – the L3 cache is doubled for Zen 2 over Zen 1.
Each full CPU, regardless of how many chiplets it has, is paired with a central IO die through Infinity Fabric links. The IO die acts as the central hub for all off-chip communications, as it houses all the PCIe lanes for the processor, as well as memory channels, and Infinity Fabric links to other chiplets or other CPUs. The IO die for the EPYC Rome processors is built on Global Foundries' 14nm process, however the consumer processor IO dies (which are smaller and contain fewer features) are built on the Global Foundries 12nm process.
The consumer processors, known as ‘Matisse’ or Ryzen 3rd Gen or Ryzen 3000-series, will be offered with up to two chiplets for sixteen cores. AMD is launching six versions of Matisse on July 7th, from six cores to sixteen cores. The six and eight-core processors have one chiplet, while above this the parts will have two chiplets, but in all cases the IO die is the same. This means that every Zen 2 based Ryzen 3000 processor will have access to 24 PCIe 4.0 lanes and dual channel memory. Based on the announcements today, the prices will range from $199 for the Ryzen 5 3600, up to $700+ for the sixteen core (we’re waiting on final confirmation of this price).
The EPYC Rome processors, built on these Zen 2 chiplets, will have up to eight of them, enabling a platform that can support up to 64 cores. As with the consumer processors, no chiplet can communicate directly with each other – each chiplet will only connect directly to the central IO die. That IO die houses links for eight memory channels, and up to 128 lanes of PCIe 4.0 connectivity.
AMD’s Roadmap
Before diving into the new product line, it is worth recapping where we currently sit in AMD’s planned roadmap.
In previous roadmaps, showcasing AMD’s movement from Zen to Zen 2 and Zen 3, the company has explained that this multi-year structure will showcase Zen in 2017, Zen 2 in 2019, and Zen 3 by 2021. The cadence isn’t exactly a year, as it has depended on AMD’s design and manufacturing abilities, as well as agreements with its partners in the foundries and the current market forces.
AMD has stated that its plan for Zen 2 was to always launch on 7nm, which ended up being TSMC’s 7nm (Global Foundries wasn’t going to be ready in time for 7nm, and ultimately pulled the plug). The next generation Zen 3 is expected to align with an updated 7nm process, and at this point AMD has not made any comment about a potential ‘Zen 2+’ design in the works, although at this point we do not expect to see one.
Beyond Zen 3, AMD has already stated that Zen 4 and Zen 5 are currently in various levels of their respective design stages, although the company has not committed to particular time frames or process node technologies. AMD has stated in the past that the paradigms of these platforms and processor designs are being set 3-5 years in advance, and the company states it has to make big bets every generation to ensure it can remain competitive.
For a small insight into Zen 4, in an interview with Forrest Norrod, SVP of AMD’s Enterprise, Embedded, and Semi-Custom group, at Computex, he exclusively revealed to AnandTech the code name of AMD’s Zen 4 EPYC processor: Genoa.
AMD EPYC CPU Codenames | |||
Gen | Year | Name | Cores |
1st | 2017 | Naples | 32 x Zen 1 |
2nd | 2019 | Rome | 64 x Zen 2 |
3rd | 2020 | Milan | ? x Zen 3 |
4th | ? | Genoa | ? x Zen 4 |
5th | ? | ? | ? x Zen 5 |
Forrest explained that the Zen 5 code name follows a similar pattern, but would not comment on the time frame for the Zen 4 product. Given that the Zen 3 design is expected mid-2020, that would put a Zen 4 product for late 2021/early 2022, if AMD follows its cadence. How this will play into AMD’s consumer roadmap plans is unclear at this point, and will depend on how AMD approaches its chiplet paradigm and any future adjustments to its packaging technology in order to enable further performance improvements.
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GreenReaper - Tuesday, June 11, 2019 - link
A lot of progress has been made. Browsers are far more multithreaded than they once were - and as web pages become more complex, that benefit can scale. Similarly, databases and rendering can scale very well over certain operations.Said scaling tends to work best for the longest operations, because they can be split up into chunks without too much overhead. The overall impact should be that there are fewer long, noticeable delays. There isn't so much progress for things that are already pretty fast - or long sequences of operations that rely on one another. (However, precomputing and prefetching can help.)
stephenbrooks - Thursday, June 13, 2019 - link
I find it surprising how they add these smallish increases onto execution width, out of order buffers, register files etc. The IPC hasn't stopped increasing, it's just slow-ish. Maybe they're fighting power and latency in those part of the core so the 2x density from a node doesn't translate fully.Santoval - Tuesday, June 11, 2019 - link
Prices should drop when the competition with Intel becomes fiercer. I don't expect that anytime soon though.. It doesn't look like Intel will manage to release Ice Lake CPUs (except apparently the -U and -Y ones they announced) this year or at all.Their 10nm+ node is still having serious issues with clocks and thermals, and the yields are much lower than TSMC's 7nm (high performance) node. So "word on the street" is that they won't release Ice Lake CPUs for desktop at all. Id est that they'll can them and release instead Tiger Lake desktop CPUs fabbed with their fixed (??) 10nm++ node variant late next year (as in Q4 2020).
piroroadkill - Wednesday, June 12, 2019 - link
You're wrong. You get more performance than Intel at a lower price. In the case of the 3950X, it's significant. To sell them cheaper would devalue an incredible product, for no reason.Targon - Thursday, June 13, 2019 - link
Ryzen 7 2700X vs. Ryzen 7 3700X. Same price, better performance. Looking at the 3800X which is $399, look at the IPC+clock speed improvements. The 3900X will obviously come at a cost, because you are getting 50% more cores for that increased price. Single threaded though....at what point do you really focus on how fast or slow a single threaded program is running in this day and age where you run dozens of processes at the same time? If you are running dozens of single threaded programs, then performance will change based on how the OS scheduler assigns them to different CPU cores.Qasar - Thursday, June 13, 2019 - link
jjj" They give us around 20% ST gains (IPC+clocks) but at a cost. " that same thing could be said about intels cpus over the last few years... how much performance increase did they give us year over year ?? all while only giving is 4 cores for the mainstream... amd's prices are just fine.. intel is the one that should be dropping their prices, some as low as the $50 you say, but most, $500 or more
Tunnah - Monday, June 10, 2019 - link
I bet now Intel is just going to completely flood ads with the title "Intel beats AMD in pure FPS tests!", because they'll get 210fps where AMD gets 200. And some people will eat it up.I'm so excited for this upgrade. Replacing a 2700K with a 3800X, where I'll not only get a doubling of cores, but clock for clock I reckon it's a 40, 50% improvement there too.
My Civ games are gonna be so zoomy now..
xrror - Monday, June 10, 2019 - link
Intel will always beat AMD ......
...
(at a price point you don't give a f*ck about) (4 digits or more)
Are you a micro-trader hardwired into the BS Stock Exchange? You think $1000+ is too much for the fully enabled processor arch you want to overclock should cost you?
Sorry, Intel doesn't have the time of day for you after 2011, after Sandy Bridge took away the ability to overclock blessed "K" skus...
oh sure, there are others. IDT and Cyrix are dead but... let me introduce you to...
AMD
xrror - Monday, June 10, 2019 - link
This isn't aimed at you Tunnah. I meant it as humor.Read my comment like some exciting infocommercial, with ... (insert commanding infomercial voice here) hehe
Makaveli - Tuesday, June 11, 2019 - link
The 2700k and the 3800X are both 8C 16T designs.