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!

 

[DrMrLordX]

At first glance, it does not look like the AM5 package has space for 3 CCDs. They would need 12c CCDs.

 

[naad]

Is there space for more than 2 8 core dies? Along with the IO die?

The better question is does the I/O die have a third GMI link for a third chiplet? Otherwise you'd be running the third chiplet through a congested GMI link and the chiplet would function for nothing but boosting cinnebench scores.

Personally I don't think it does, 8C + 16C might be in the works for zen5 tho.

 

[SteinFG]

Is there any chance AMD will release a 24core or 32core Zen 4 CPU during the product cycle? What is the maximum theoretical core count for a Zen 4 CPU's on the consumer grade motherboard/chipset?

No chance, 16 cores is the max, that's set in stone for zen 4 on desktop.
MAYBE with zen 5 in 2024 we'll get 32 cores (2 CCDs, each with 16 cores, on 3nm), but that's just a rumor right now.

The better question is does the I/O die have a third GMI link for a third chiplet? Otherwise you'd be running the third chiplet through a congested GMI link and the chiplet would function for nothing but boosting cinnebench scores.

I assume no. Also, there's no "congested" GMI links, there's always 1 dedicated link for each CCD. If you're thinking of epyc, the io die on 7002/7003 has 8 links.

 

[Timmah!]

View attachment 65548

OK, so technically it happened, but it was so long ago, that its hardly relevant to current situation.
If anything, this proves that AMD had no issue to ask 1300 USD for their top client CPU, and at the time when that amount of money had more value compared to nowadays.

 

[poke01]

I am waiting for Zen 4 in laptops. The efficiency of Zen will help AMD in the laptop space

 

[Timmah!]

No chance, 16 cores is the max, that's set in stone for zen 4 on desktop.
MAYBE with zen 5 in 2024 we'll get 32 cores (2 CCDs, each with 16 cores, on 3nm), but that's just a rumor right now.

I assume no. Also, there's no "congested" GMI links, there's always 1 dedicated link for each CCD. If you're thinking of epyc, the io die on 7002/7003 has 8 links.

I think we will see more than 16C on Zen5 or whatever the next smaller node than 5nm generation will be - then it will be either more cores per CCD or smaller CCDs, so more of them will fit onto the PCB.
I can see this happening at the time Intel will release Arrow Lake (or whatever is the codename of the rumored 8P+32E chip).
Unless they think 2 channel memory is not enough for 24/32 cores and it will only happen with next, post-AM5, client platform, that will maybe jump to 4 channels.

To be fair, thinking this will happen and not in the very far future (since the reason why its not happening now is not that its technologically impossible) kinda spoils the enjoyment from possibly getting Zen4. I mean, there is always something new and better coming, so you could be waiting forever, but there are sort of "supercycles", when you get bigger jumps and more value than usual...while its not sure whether Zen5 will be one, its sure as hell that Zen4, sticking to same number of cores as last 2 gens, wont be one.

 

[InstrEd]

I am waiting for Zen 4 in laptops. The efficiency of Zen will help AMD in the laptop space

Me 2
Hopefully there won't be a shortage of mobile zen 4 chips. At least in my view we have some nice competition in mobile space. It would be nice to get a decent 2n1 laptop with great battery life without breaking the piggy bank.

 

[Ranulf]

I am waiting for Zen 4 in laptops. The efficiency of Zen will help AMD in the laptop space

You and everyone else that says this every year. Myself included. I'll wait till it actually happens though. Maybe this will be the year of the Ryzen apu and laptop chips taking the world by storm.

 

[InstrEd]

Hopefully Zen 4 delivers the goods😀

 

[biostud]

You and everyone else that says this every year. Myself included. I'll wait till it actually happens though. Maybe this will be the year of the Ryzen apu and laptop chips taking the world by storm.

They at least can now use the regular ryzen processors clocked/voltage regulated with a mGPU for high performance laptops, and a Zen4 based APU for mixed use. It will be possible to have a mobile version of a 7800X3D in a gaming laptop.

 

[DrMrLordX]

Hopefully there won't be a shortage of mobile zen 4 chips.

Don't hold your breath waiting for that. Getting your hands on a Rembrandt laptop is hard enough already. Cezanne was similarly difficult-to-get for at least 6 months after its launch.

 

[FangBLade]

Don't hold your breath waiting for that. Getting your hands on a Rembrandt laptop is hard enough already. Cezanne was similarly difficult-to-get for at least 6 months after its launch.

Yeah, i'm looking for a new laptop with 6000 series and availability is disaster, couple of expensive models with crap display and 8gb ram. I hope situation will be better by end of the year.

 

[Markfw]

Yeah, i'm looking for a new laptop with 6000 series and availability is disaster, couple of expensive models with crap display and 8gb ram. I hope situation will be better by end of the year.

I have been waiting over a month for my 6800u laptop to ship....16 gig ram and 512 gig M.2

 

[InstrEd]

Give us a review when you finally get your laptop

 

[TESKATLIPOKA]

I am also thinking about upgrading to a compact Phoenix Point laptop, If It manages to deliver 3050Ti 45W level of performance within 45W TDP.
Availability on the other hand will be certainly a big problem.

P.S. I expect a pretty decent performance increase due to higher clocks thanks to better process.

 

[xilli_fiberbit]

A reviewer has already a motherboard with X670E in hands :

https://twitter.com/x/status/1556884925927682048

 

[moinmoin]

Reviewers' getting hardware this early is a good sign. Sounds like this could become a smooth launch.

 

[Det0x]

DDR5-6000 Memory To Be The Sweet Spot For AMD Ryzen 7000 “Zen 4” CPUs, Will Offer 1:1 Infinity Fabric Ratio With EXPO

From what we have learned, it looks like AMD's Ryzen 7000 Zen 4 CPUs will most definitely have DDR5-6000 as their sweet spot, allowing a 1:1 IFC ratio. A 1:1 ratio means that the memory is running with the same frequency as the memory controller on the processor and that should offer a best-case scenario. With Alder, Intel has broken down the memory ranks into two categories, a 2:1 mode known as Gear 2 which is the default for DDR5, and a 4:1 model known as Gear 4. The advantage that a 1:1 brings to the table is that it will allow for lower latencies and a balanced speed while a higher ratio will allow for better overclocking, & faster data transfer rates but will also lead to poor latencies.

So DDR5-6000 for AMD Ryzen 7000 "Zen 4" CPUs already sounds great for AM5 and that will be DDR5-5600 by default. Higher frequency DIMMs are supported but as soon as you go above the DDR5-6000 limit, you will drop down to a 1:2 IFC. We are told that DDR5-6400 running at 1:2 will produce poor results and is not recommended if you are looking for better gaming performance.

This is good news for the average user i guess, but alittle boring for us that like to tweak and overclock the memory manually..
Also made the memory recommending for new buyers much easier, just get memory @ 6000MT/s with lowest possible timings and enable XMP/EXPO and be done with it

It also sounds like the best overclocking boards such as Asus APEX will use the B650E chipset instead of X670E.

Furthermore, it also looks like X670E/X670, while designed for overclocking, won't actually get the best memory overclocking motherboards as those are reserved for the B650E chipsets. Gigabyte confirmed that they will be offering the Tachyon with two DDR5 DIMM slots on a B650(E) chipset but we will have to wait sometime to see that motherboard in action. The X670E and X670 boards will support both overclocking and undervolting for Ryzen 7000 "Zen 4" CPUs but to what extent that is allowed purely depends on AMD.

 

[MadRat]

You would think that in 2022 they could figure out how to soften latency during asynchronous memory transfers by now.

 

[biostud]

With the 7950X priced @ $799 there should be room for a 7950X3D @ $1099 (and the 7800X3D @ $549)

 

[Det0x]

You would think that in 2022 they could figure out how to soften latency during asynchronous memory transfers by now.

Yes its very strange Alder and soon to be Raptor lake have to run DDR5 @ gear2 all the time.. Cant boot 4800MT/s gear1 (1:1)

We saw a earlier leak from graymon55 where he wrote 58ns @ 6400MT/s, i wonder if this was in 1:1 or 1:2 mode

https://twitter.com/x/status/1555517933493047296

 

[Timmah!]

With the 7950X priced @ $799 there should be room for a 7950X3D @ $1099 (and the 7800X3D @ $549)

i think 999 for x3D is more likely.

 

[DrMrLordX]

This is good news for the average user i guess, but alittle boring for us that like to tweak and overclock the memory manually..
Also made the memory recommending for new buyers much easier, just get memory @ 6000MT/s with lowest possible timings and enable XMP/EXPO and be done with it

Or buy the best-available kit, downclock it to DDR5-6000, and hand-tune for timings better than what the DDR5-6000 kits allow.

 

[Timorous]

Or buy the best-available kit, downclock it to DDR5-6000, and hand-tune for timings better than what the DDR5-6000 kits allow.

Or wait for Zen 5 and for DDR5 to be far more mature.

 

[DrMrLordX]

Or wait for Zen 5 and for DDR5 to be far more mature.

That takes too long. It's going to be bad enough for me to wait for November (or whenever) to get my hands on Raphael-X.