News An interview with Mike Clark, the Father of Zen — 'Zen Daddy' says 3nm Zen 5 is coming faster than you think; also talks compact cores for desktop...

PaulAlcorn

Managing Editor: News and Emerging Technology
Editor
Feb 24, 2015
876
394
19,360
Does Jim Keller know AMD is trying to give Mike Clark credit as the creator of the Zen Architecture?
Jim seems like the kind of guy who would sue over that kind of thing.
This is a very common misconception. However, Mike Clark was the lead architect from day one. I was in the audience when he introduced Zen 1 at Hot Chips in 2016 as the lead architect. I even interviewed him backstage after the presentation. (Fun fact: I interviewed him in the same green room Steve Jobs used before his most famous presentations).

https://www.tomshardware.com/news/amd-zen-cpu-microarchitecture,32540.html

Keller, to my knowledge, worked on the Infinity Fabric. He made contributions there, but was not the lead architect.
 
Last edited:

bit_user

Titan
Ambassador
Does Jim Keller know AMD is trying to give Mike Clark credit as the creator of the Zen Architecture?
Yes.

Ian Cutress: A few people consider you 'The Father of Zen', do you think you’d scribe to that position? Or should that go to somebody else?

Jim Keller: Perhaps one of the uncles. There were a lot of really great people on Zen. There was a methodology team that was worldwide, the SoC team was partly in Austin and partly in India, the floating-point cache was done in Colorado, the core execution front end was in Austin, the Arm front end was in Sunnyvale, and we had good technical leaders. I was in daily communication for a while with Suzanne Plummer and Steve Hale, who kind of built the front end of the Zen core, and the Colorado team. It was really good people. Mike Clark's a great architect, so we had a lot of fun, and success. Success has a lot of authors - failure has one. So that was a success. Then some teams stepped up - we moved Excavator to the Boston team, where they took over finishing the design and the physical stuff, Harry Fair and his guys did a great job on that. So there were some fairly stressful organizational changes that we did, going through that. The team all came together, so I think there was a lot of camaraderie in it. So I won't claim to be the ‘father’ - I was brought in, you know, as the instigator and the chief nudge, but part architect part transformational leader. That was fun.

Source: https://www.anandtech.com/show/16762/an-anandtech-interview-with-jim-keller-laziest-person-at-tesla

Jim seems like the kind of guy who would sue over that kind of thing.
I hope you're being sarcastic, because he seems pretty chill to me.
 
Last edited:

bit_user

Titan
Ambassador
Thanks for the interview @PaulAlcorn !

If anyone is interested in some more in-depth details about the Zen 5 architecture, Chips & Cheese also got some fairly forthcoming answers to their own set of rather in-depth questions:


I thought a very interesting revelation was how the dual decoders function, both in single-threaded mode and SMT mode.

There's also a very interesting point made about how the architecture needed to be overhauled, in order to support the next several generations of cores. It reminded me of another quote from Jim (emphasis added):

Jim Keller: So when you build a new computer, and Zen was a new computer, there was already work underway. You build in basically a roadmap, so I was thinking about what we were going to do for five years, chip after chip. We did this at Apple too when we built the first big core at Apple - we built big bones [into the design]. When you make a computer faster, there's two ways to do it - you make the fundamental structure bigger, or you tweak features, and Zen had a big structure. Then there were obvious things to do for several generations to follow. They've been following through on that.

So at some point, they will have to do another big rewrite and change. I don't know if they started that yet. What we had planned for the architectural performance improvements were fairly large, over a couple of years, and they seem to be doing a great job of executing to that. But I've been out of there for a while - four or five years now.

Source: https://www.anandtech.com/show/16762/an-anandtech-interview-with-jim-keller-laziest-person-at-tesla

So, I think it's a pretty safe bet that Zen 5 is that that "big rewrite and change". If you read/watch the C&C interview with Mike, that's sure what it sounds like. Also, considering that Zen 4 was cast as a more minor revision that I think focused mostly on the front end.
 
This is a very common misconception. However, Mike Clark was the lead architect from day one. I was in the audience when he introduced Zen 1 at Hot Chips in 2016 as the lead architect. I even interviewed him backstage after the presentation. (Fun fact: I interviewed him in the same green room Steve Jobs used before his most famous presentations).

https://www.tomshardware.com/news/amd-zen-cpu-microarchitecture,32540.html

Keller, to my knowledge, worked on the Infinity Fabric. He made contributions there, but was not the lead architect.
This is a huge misconception that people just parrot on the internet.

Thanks for this post to set things straight.

And AMD stop it I want to go Zen 5 and more so X3D version but if there is going to be a 3nm version.... I may wait.
 
  • Like
Reactions: Bamda and bit_user

bit_user

Titan
Ambassador
This is a huge misconception that people just parrot on the internet.
I think the issue is that they want one name to attach to Zen. Jim Keller was around for much of its development, and definitely the most well-known among the principals involved, so he ends up getting attached to it.

His actual title was:

Corporate VP & Chief Architect
AMD · Full-time 2012 - 2015 · 3 yrs

Source: https://www.linkedin.com/in/jimbkeller/details/experience/ (requires sign-in)

BTW, I think another big misconception is that Zen was instigated by Lisa Su. However, both the Zen project and Jim Keller's tenure pre-dated her role as CEO. I do think she probably deserves some credit for giving it the oxygen it needed to be successful, which included a couple big financial deals, but it was something she inherited rather than helped originate.

Keller, to my knowledge, worked on the Infinity Fabric. He made contributions there, but was not the lead architect.
I just took a look through the patents filed by James (B.) Keller, and all the ones at Advanced Micro Devices, Inc. were from his first stint there. So, I think that says he was in a more high-level, leadership role. And if he did contribute any novel ideas, he let the folks under him take the credit.

Once you've got about a hundred patents, what's a few more?

And AMD stop it I want to go Zen 5 and more so X3D version but if there is going to be a 3nm version.... I may wait.
There's always something better, not too far around the corner. You just have to decide when either the need is great enough, or the benefit of upgrading outweighs the costs. The advantages of upgrading sooner is that you get more time to enjoy the upgrade and it leaves more room for improvement between it and your next upgrade.
 
Last edited:

usertests

Distinguished
Mar 8, 2013
969
858
19,760
so you may as well have used a combat core
I too, want to see combat cores.

And AMD stop it I want to go Zen 5 and more so X3D version but if there is going to be a 3nm version.... I may wait.
I don't see any confirmation of another desktop CPU using 3nm, or even Zen 5c.

What's likely is that Zen 5c chiplets for Epyc are made on 3nm. Anything else, don't hold your breath.
 
There's always something better, not too far around the corner. You just have to decide when either the need is great enough, or the benefit of upgrading outweighs the costs. The advantages of upgrading sooner is that you get more time to enjoy the upgrade and it leaves more room for improvement between it and your next upgrade.
True. However, you may be lucky with a generation that lasts "forever" - People who got a Sandy Bridge i7 were content for almost a decade, those with a Kaby Lake desktop much less so (no Win11 support, quad core when things soon required 6 hardware cores). Same, If you got a Ryzen 1600 AF you were good for quite some time, but the earlier models not as much - getting a 2700X in comparison was good ! Zen2 was also a bit of a letdown, being midway between early Zen and the fantastic Zen3. On graphics cards, owners of Radeon HD 48x0 were happy for a long, time, so were those who got a Geforce GTX 8800... Owners of Polaris GPUs were laughed at at the beginning, but after 2 GPU krashes, much less so - and so on.
 
  • Like
Reactions: NinoPino

bit_user

Titan
Ambassador
you may be lucky with a generation that lasts "forever"
Yeah, I get that. It's often hard to tell when those products will land, however. Part of it is that something like Alder Lake arrives and seems revolutionary, but then Raptor Lake comes along and really makes the architecture sing. But, now that the reliability concerns started to mount, it's starting to look like Gen 12 really might have been one of those golden generations.

Zen2 was also a bit of a letdown, being midway between early Zen and the fantastic Zen3.
Really? I don't recall anyone complaining about Zen 2, at the time. It's just that once Zen 3 launched, its predecessor lost a little of its luster.

What I'd say is: if someone has an inside scoop on a new product launch that seems like a big leap, and they can afford to wait, then maybe do. But, if all you have to go on is some nebulous tidbits and the successor is decently far in the future, then probably don't put off an upgrade if you really need/want to do it sooner.

BTW, @Makaveli I'm pretty sure the 3nm product is the Zen 5C chiplet. That explains why they're "basically arriving on top of each other." It wouldn't
make sense otherwise, as bringing the N4P chiplet to market would mean following through on a product that's almost immediately obsolete.
 
Last edited:
I too, want to see combat cores.


I don't see any confirmation of another desktop CPU using 3nm, or even Zen 5c.

What's likely is that Zen 5c chiplets for Epyc are made on 3nm. Anything else, don't hold your breath.
He didn't confirm anything but mention Zen 5 was made for both nodes.

My gut tells me we will see desktop on 3nm in a refresh at sometimes later 2025 :)
 
What I'd say is: if someone has an inside scoop on a new product launch that seems like a big leap, and they can afford to wait, then maybe do. But, if all you have to go on is some nebulous tidbits and the successor is decently far in the future, then probably don't put off an upgrade if you really need/want to do it sooner.
Getting a new PC/parts is a balancing act of performance gained, versus drawbacks of change, versus cost. Personally, I went from the venerable i5 3570k OCed at 4.5 to a 3900x on July 7th 2019. The 3570k was really nice for the 7 years I had used it, but i found the need for more than 4c/4t. It was a massive upgrade over what I had. I have since got the 5800X3D on launch day which has been even more fantastic. I typically go years between my upgrades and I usually prefer getting into a more mature platform. I like to make the most of my parts for as long as possible. I really want to build an SFF PC just because, but I think I won't because I have very little use for even more performance. I will probably be on zen 3 for a few more years to come.
 
Last edited:
Getting a new PC/parts is a balancing act of performance gained, versus drawbacks of change, versus cost. Personally, I went from the venerable i5 3570k OCed at 4.5 to a 3900x on July 7th. The 3570k was really nice for the 7 years I had used it, but i found the need for more than 4c/4t. It was a massive upgrade over what I had. I have since got the 5800X3D on launch day which has been even more fantastic. I typically go years between my upgrades and I usually prefer getting into a more mature platform. I like to make the most of my parts for as long as possible. I really want to build an SFF PC just because, but I think I won't because I have very little use for even more performance. I will probably be on zen 3 for a few more years to come.
This is the best way to do it I find Gen on Gen upgrade are a waste. The only exception to this is the highend tier GPU's because you generally get a far bigger uplit on them than on cpu's per generation.
 
  • Like
Reactions: helper800

overlord

Distinguished
Aug 29, 2001
122
6
18,685
Last edited:
Really? I don't recall anyone complaining about Zen 2, at the time. It's just that once Zen 3 launched, its predecessor lost a little of its luster.
Zen 2 was nice - at the time. But once Zen 3 came out, it lost all interest outside of mobile space (on handhelds, with how much more compact it was, it managed to keep good performance per watt VS Zen 3). Zen 3, on the other hand, stayed current for a few years - the fact that it was the ultimate µarch on the very long staying AM4 does count for a lot of it - got a Zen PC in 2017 ? Throw a Zen 3 chip in it in 2024 and stay current for 3 more years ! If you land a 5700X3D, you can even have leading performance in games for not a lot of money.
 
  • Like
Reactions: bit_user

systemBuilder_49

Distinguished
Dec 9, 2010
105
40
18,620
And AMD stop it I want to go Zen 5 and more so X3D version but if there is going to be a 3nm version.... I may wait.
I think only Strix Halo will be three nanometers. They need that shrink to save power for the huge GPU! Also, i think Strix Halo might be only for oem (console, handheld) partners - i dont think it will be available for laptops or mini PCs, we'll have to wait and see about that ...
 
Last edited:
Getting a new PC/parts is a balancing act of performance gained, versus drawbacks of change, versus cost. Personally, I went from the venerable i5 3570k OCed at 4.5 to a 3900x on July 7th 2019. The 3570k was really nice for the 7 years I had used it, but i found the need for more than 4c/4t. It was a massive upgrade over what I had.
I went from an Athlon XP 3000+ to an Intel i7-4770k in 2013. Now that 4770k is getting long in the tooth and I need more than 32GB RAM for a virtual home lab. I'm looking forward to the 9700X as Zen 5 seems to be that CPU uArch that will be good for another decade.
 
I can see AMD following Intel with core counts for consumer market, at some point performance cores will standardise probably at 6 or 8, with or without HT, at higher clock speeds and it will be the efficiency cores that will increase in number definitely with HT and at will be speed capped with very tight variable power usage.
 

usertests

Distinguished
Mar 8, 2013
969
858
19,760
I think only Strix Halo will be three nanometers. They need that shrink to save power for the huge GPU! Also, i think Strix Halo might be only for oem (console, handheld) partners - i dont think it will be available for laptops or mini PCs, we'll have to wait and see about that ...
Who do you think makes laptops and mini PCs?

Strix Halo is for laptops before anything else, challenging laptops with dGPUs, which are expensive products that can use a lot of power. They are often treated like desktops and plugged in constantly.

It may do well in handhelds, but it could use more power than desired to get good results. We will have to see about that one. I don't see it being relevant to whatever non-handheld "consoles" means. It won't be found in a PS5 Pro for instance.

If you are right about Strix Halo using TSMC N3 chiplets for the CPU, that would be exciting. I think there was a rumor that Strix Halo will use all Zen 5 cores, but not the same chiplet as Ryzen 9000. If that's true, then the interview answer about Zen 5 on two nodes makes much more sense. But I still think it could refer to Zen 5c on 3nm.

I can see AMD following Intel with core counts for consumer market, at some point performance cores will standardise probably at 6 or 8, with or without HT, at higher clock speeds and it will be the efficiency cores that will increase in number definitely with HT and at will be speed capped with very tight variable power usage.
8 performance cores needs to be easy to get to, if not the minimum. After that, slower cores are going to be fine for most. This is at least true until a couple of years after the release of next-gen consoles.
 

Bamda

Distinguished
Apr 17, 2017
114
38
18,610
I'm pleased that AMD has a wealth of talented leaders. After switching from Intel to the AM4 family of CPUs, I'm happy with my decision, especially given the current events at Intel. I'm looking forward to upgrading my system with the AM5 socket replacement they develop.