Discussion Speculation: Zen 4 (EPYC 4 "Genoa", Ryzen 7000, etc.)

[Vattila]

Except for the details about the improvements in the microarchitecture, we now know pretty well what to expect with Zen 3.

The leaked presentation by AMD Senior Manager Martin Hilgeman shows that EPYC 3 "Milan" will, as promised and expected, reuse the current platform (SP3), and the system architecture and packaging looks to be the same, with the same 9-die chiplet design and the same maximum core and thread-count (no SMT-4, contrary to rumour). The biggest change revealed so far is the enlargement of the compute complex from 4 cores to 8 cores, all sharing a larger L3 cache ("32+ MB", likely to double to 64 MB, I think).

Hilgeman's slides did also show that EPYC 4 "Genoa" is in the definition phase (or was at the time of the presentation in September, at least), and will come with a new platform (SP5), with new memory support (likely DDR5).

What else do you think we will see with Zen 4? PCI-Express 5 support? Increased core-count? 4-way SMT? New packaging (interposer, 2.5D, 3D)? Integrated memory on package (HBM)?

Vote in the poll and share your thoughts!

 

[DisEnchantment]

https://twitter.com/x/status/1508785076712062991

So it should be early/mid Q3

Hmmm ... Greymon has not been on top of leaks lately though. He is just guessing at this point.
Seems only Execufix is consistent, but he does not want to touch release date because according to him it "can change at any moment"

 

[leoneazzurro]

Hmmm ... Greymon has not been on top of leaks lately though. He is just guessing at this point.
Seems only Execufix is consistent, but he does not want to touch release date because according to him it "can change at any moment"

He also said in the discussion that he got information that the packaging plant is getting ready to produce Raphael next month or early May.
It's quite clear that the source of his information (or the chinese forum posters he gets the info from) can be tracked to the packaging plant instead of the foundry.

 

[nicalandia]

I find this very informative.

How It's Built: AMD 3D V-Cache Technology

 

[Markfw]

I find this very informative.

How It's Built: AMD 3D V-Cache Technology

No captions available, so its NOT very informative for deaf people like me. I hate videos. Why not good old web pages ????

 

[Saylick]

No captions available, so its NOT very informative for deaf people like me. I hate videos. Why not good old web pages ????

You're not missing out on much. Anything you need to know about V-cache, you've probably read somewhere as an article before.

 

[ondma]

I suppose it is good as a technical exercise, but not sure I see the point of the 3d cache for the 5800x. Expensive (I assume), runs hotter, lower clocks and cant be overclocked. It would have been a nice counter to AL a few months ago, but now seems to make much more sense on the desktop to simply wait for Zen 4, at least if half the rumors of increased performance are true.

 

[Markfw]

I suppose it is good as a technical exercise, but not sure I see the point of the 3d cache for the 5800x. Expensive (I assume), runs hotter, lower clocks and cant be overclocked. It would have been a nice counter to AL a few months ago, but now seems to make much more sense on the desktop to simply wait for Zen 4, at least if half the rumors of increased performance are true.

It is a response to ADL, to regain the gaming crown. The only uncontested win for ADL. This is my opinion of course, but I think most of us know this to be true. Yes, it would have been nice to have it a few months ago, but for many reasons, it was not possible. Intel jacking the watts up on ADL to win benchmarks could have been a surprise to AMD, is it seems silly to ruin a good CPU by giving it too much juice.

 

[Exist50]

It is a response to ADL, to regain the gaming crown. The only uncontested win for ADL. This is my opinion of course, but I think most of us know this to be true. Yes, it would have been nice to have it a few months ago, but for many reasons, it was not possible. Intel jacking the watts up on ADL to win benchmarks could have been a surprise to AMD, is it seems silly to ruin a good CPU by giving it too much juice.

CML and RKL are basically the same as ADL from a boost power perspective. No reasonable person would have assumed that Intel would suddenly cut back much on power.

3D cache is just very low volume at the moment, and the majority will be dedicated to Milan-X where it gives the most value.

 

[maddie]

I suppose it is good as a technical exercise, but not sure I see the point of the 3d cache for the 5800x. Expensive (I assume), runs hotter, lower clocks and cant be overclocked. It would have been a nice counter to AL a few months ago, but now seems to make much more sense on the desktop to simply wait for Zen 4, at least if half the rumors of increased performance are true.

The last hurrah for AM4 sockets, out with a bang. You can use the rest of your present system. No DDR5 ram + no new motherboard. The fact that they are making it compatible with the earliest chipsets can tell any slightly critical thinker that they expect the (upgrade CPU market) to be substantial.

 

[Markfw]

CML and RKL are basically the same as ADL from a boost power perspective. No reasonably person would have assumed that Intel would suddenly cut back much on power.

3D cache is just very low volume at the moment, and the majority will be dedicated to Milan-X where it gives the most value.

Since that was a bad thing in the previous series (IMO), one would think that the new line would be low power, and improvement. They needed the high power before, on 14nm+++++, but on 10nm one would think they would have cut it back to be a better value. But they just wanted to win a few benchmarks more, so they jacked up the power.

I have not figured out how to do this on my 12700F, but from what I read, ADL CAN be quite good at lower power, just can't perform like a 5950x.

Edit: except for gaming, ADL wins low or high power I think.

 

[nicalandia]

I suppose it is good as a technical exercise, but not sure I see the point of the 3d cache for the 5800x. Expensive (I assume), runs hotter, lower clocks and cant be overclocked.

$449 for the Highest Performance 8C/16T that has ever been released? Mind you the 1800X was released at $499 and the 6900K was upwards $1,000. If you are on a budget the 3700X or 3900X are pretty good.

 

[DrMrLordX]

I find this very informative.

How It's Built: AMD 3D V-Cache Technology

Kind of the wrong thread for that no?

 

[nicalandia]

Kind of the wrong thread for that no?

True.. I missed my morning coffee

 

[eek2121]

Since that was a bad thing in the previous series (IMO), one would think that the new line would be low power, and improvement. They needed the high power before, on 14nm+++++, but on 10nm one would think they would have cut it back to be a better value. But they just wanted to win a few benchmarks more, so they jacked up the power.

I have not figured out how to do this on my 12700F, but from what I read, ADL CAN be quite good at lower power, just can't perform like a 5950x.

Edit: except for gaming, ADL wins low or high power I think.

Going to disagree. If you leave ADL-S at a PL2 of 200+ watts it is still going to use more power than the 5950x when gaming. I've seen comparisons of ADL-S using 160W and a Ryzen 5950X using 93W. The performance difference between the two was around 12%. That makes Ryzen the more efficient chip.

Reviewers should get into in depth power testing, but thus far nobody reliable has done so.

 

[Markfw]

Going to disagree. If you leave ADL-S at a PL2 of 200+ watts it is still going to use more power than the 5950x when gaming. I've seen comparisons of ADL-S using 160W and a Ryzen 5950X using 93W. The performance difference between the two was around 12%. That makes Ryzen the more efficient chip.

Reviewers should get into in depth power testing, but thus far nobody reliable has done so.

I guess the comparison I saw was a 12700k and a 5900x or 5950x. I will not argue they use more, I just thought I read in gaming, they did not take that much. I will look again.

Edit: Found it, yes more by 7 watts, almost random error... Here:

Page 32 - Question - Alder Lake - Official Thread

Page 32 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

forums.anandtech.com

But this is a Zen 4 thread, so no more comments from me on that subject, however, I guess its relevant when I see 170 watt Zen 4 ????

 

[jamescox]

I guess the comparison I saw was a 12700k and a 5900x or 5950x. I will not argue they use more, I just thought I read in gaming, they did not take that much. I will look again.

Edit: Found it, yes more by 7 watts, almost random error... Here:

Page 32 - Question - Alder Lake - Official Thread

Page 32 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

forums.anandtech.com

But this is a Zen 4 thread, so no more comments from me on that subject, however, I guess its relevant when I see 170 watt Zen 4 ????

Was there any consensus on whether 16-core Zen 4 at 5 GHz could actually draw 170 Watts? I didn’t think AMD had really shown off frequencies much previously, so perhaps there will be higher clocks than expected.

It would be great if they go to 24 core, but it seems like there is a possibility that 170 W is for a farther future product. Zen 5 will likely have massive FP capabilities among other things, so making the socket capable of supporting it would likely require a higher TDP than Zen 4 is capable of.

AMD really could stand to do a true half Epyc socket, perhaps under a new name. Threadripper is fine for HEDT, but they could use a real workstation product line. I was just looking at a few places that do workstations for business and they seem to still be rather pitiful Intel offerings. If they have an in between socket with Zen 4 rather than weird situation with Threadripper and Threadripper Pro, then would they go beyond 16 cores for AM5?

 

[biostud]

How much power does the IO use and how much does the CCX use?

 

[Ajay]

Was there any consensus on whether 16-core Zen 4 at 5 GHz could actually draw 170 Watts? I didn’t think AMD had really shown off frequencies much previously, so perhaps there will be higher clocks than expected.

Depending on how AVX-512 is implemented, and the workload being run, I suppose a 16 core Zen4 could have a peak power of 170W. Of course, that's socket power, which means the actual max power load could be high as it is for Zen2/3.

It would be great if they go to 24 core, but it seems like there is a possibility that 170 W is for a farther future product

A lot of task would be bandwidth limited with 24 cores, IMHO. I suppose this question will be put to bed once we have a verified layout for Raphael.

Threadripper is fine for HEDT, but they could use a real workstation product line. I was just looking at a few places that do workstations for business and they seem to still be rather pitiful Intel offerings. If they have an in between socket with Zen 4 rather than weird situation with Threadripper and Threadripper Pro

It seems that AMD is only interested in the high performance workstation market with Threadripper Pro; which actually puts it out of the range of a true HEDT system for the small 'prosumer' market . They are probably using chiplets that don't quite meet the standards for chiplets used in Epyc CPUs. Hence the long delay - Epyc is so much more profitable with it's high demand rate, that Zen3 based workstations didn't make business sense until Zen4 based Epyc CPUs started trickling into the server market.

IMHO.

 

[ondma]

$449 for the Highest Performance 8C/16T that has ever been released? Mind you the 1800X was released at $499 and the 6900K was upwards $1,000. If you are on a budget the 3700X or 3900X are pretty good.

Not saying it is a bad chip, or that it is not a good value relative to historical levels. Still begs the question as to why one would not just wait for Zen 4 with a more modern platform. If Zen 4 is all that it is hyped up to be, 5800x 3d will be the "fastest 8 core ever released" for, what only a few months? I suppose you could make a case for it if you wanted to upgrade without changing the motherboard.

 

[Thibsie]

Well, many people can't just change all their platform just like that. I only got my 2600+ a bit more than a year ago and upgraded to 5600+ 5 months ago.

Changing mobo+RAM+CPU is just not possible. GPU is a lot more urgent. If upgrade (but GPU) there is, it will be 5800+ or 5950.

 

[nicalandia]

Well, many people can't just change all their platform just like that. I only got my 2600+ a bit more than a year ago and upgraded to 5600+ 5 months ago.

Changing mobo+RAM+CPU is just not possible. GPU is a lot more urgent. If upgrade (but GPU) there is, it will be 5800+ or 5950.

People with a sturdy MB could get a 5800X3D and a 6800XT and be Set for many years to come.

 

[Thibsie]

People with a sturdy MB could get a 5800X3D and a 6800XT and be Set for many years to come.

Absolutely.
My 1060gtx (6G fortunately) gets old. My 5600x though (or a 5800x3d for that matter) isn't a limiting factor right now.

 

[nicalandia]

Absolutely.
My 1060gtx (6G fortunately) gets old. My 5600x though (or a 5800x3d for that matter) isn't a limiting factor right now.

I don't get why people keep bringing Zen4, DDR5 Early Adopter Buggs, Early AM5 MB will not compared to the solid and tested AM4 boards with world class gaming the Zen3 brings, it's not like the CPU will become a bottle neck for a 6800XT of RTX 3080 in the next few years.

 

[Mopetar]

I don't get why people keep bringing Zen4, DDR5 Early Adopter Buggs, Early AM5 MB will not compared to the solid and tested AM4 boards with world class gaming the Zen3 brings, it's not like the CPU will become a bottle neck for a 6800XT of RTX 3080 in the next few years.

It likely would be at 1080p in some titles. If that's an issue though Zen 3D is certainly an option.

However, if the CPU weren't already a bottleneck then we wouldn't be able to see gains with Zen 3D.

 

[biostud]

I don't get why people keep bringing Zen4, DDR5 Early Adopter Buggs, Early AM5 MB will not compared to the solid and tested AM4 boards with world class gaming the Zen3 brings, it's not like the CPU will become a bottle neck for a 6800XT of RTX 3080 in the next few years.

Because AM4 is EOL while an AM5 setup will be able to upgrade the CPU in the future.
And while there will be bugs, it is seldom system breaking bugs.