AMD's Zen 6-based desktop processors may feature up to 24 cores

Elusive Ruse said:

16 cores is not gonna cut it for the top offering in 2026.

except in gaming it doesn't matter (no game really ever uses over 8)...and if you want productivity TR already exists (even if not as modern still monstrous)

hotaru251 said:

except in gaming it doesn't matter (no game really ever uses over 8)...and if you want productivity TR already exists (even if not as modern still monstrous)

I disagree . Threadrippers are expensive for small businesses. entry level 24 cores Ryzens are welcomed.

I could see a 12 core CCD on the horizon, but my concern becomes the cost of entry factor. The lowest available consumer chips have launched at relatively high prices since Zen 3 and now those core counts would be higher. While I'm sure there's plenty of margin on all of these parts it would mean AMD eating into them a bit to keep current pricing given a newer node and larger die.

The other concern comes in at the top end with the question of memory bandwidth. Currently they're supporting 16 cores on 5200/5600 and this would go up to 24 cores on 6400 most likely (though with clock drivers having better availability maybe 7200). That means a 50% core count increase while adding 14-29% bandwidth. It's not guaranteed that this will be a problem, but it was starting to be an issue with Zen 3 (resolved with the move to DDR5 with Zen 4+).

Overall moving the 8 core parts to 12 would be a pretty nice MT benefit, and the lower dual CCD part would no longer be hampered by 6 core CCDs so that's good as well. It's just at the low and high end where questions remain.

Of course without more PCIe lanes or at least a PCIe 5.0 link to the chipset(s) the productivity improvements brought with higher core counts is still lacking.

thestryker said:

Of course without more PCIe lanes or at least a PCIe 5.0 link to the chipset(s) the productivity improvements brought with higher core counts is still lacking.

This is probably the biggest sore in the current crop of AM5 chipsets. I can’t believe motherboard manufacturers are boasting about having three extra PCIe 4.0 M.2 slots, when they are all funneled through a single PCIe 4.0 \00d7 4 link, shared with all the SATA, USB, LAN, and Wi-Fi traffic. It’s not even unrealistic that one might occasionally utilize all of the bandwidth available and bottleneck one thing or another.

It’s the same situation with Thunderbolt 5, the only implementation being a controller with a PCIe 4.0 \00d7 4 (nominally 64 Gb/s) host interface, which falls short supporting the even basic 80 Gb/s of data (a.k.a., no video) traffic of a single Thunderbolt connection.

hotaru251 said:

except in gaming it doesn't matter (no game really ever uses over 8)...and if you want productivity TR already exists (even if not as modern still monstrous)

This post doesn’t make sense, especially as a retort to my statement.

thestryker said:

I could see a 12 core CCD on the horizon, but my concern becomes the cost of entry factor. The lowest available consumer chips have launched at relatively high prices since Zen 3 and now those core counts would be higher.

A couple of points:
Zen 5 will probably have a long production life, just as AMD is continuing to sell Zen 3 CPUs for the budget-conscious, today.
AMD can continue to offer APUs as the lower-tier of their AM5 offerings.

thestryker said:

The other concern comes in at the top end with the question of memory bandwidth. Currently they're supporting 16 cores on 5200/5600 and this would go up to 24 cores on 6400 most likely (though with clock drivers having better availability maybe 7200). That means a 50% core count increase while adding 14-29% bandwidth. It's not guaranteed that this will be a problem, but it was starting to be an issue with Zen 3 (resolved with the move to DDR5 with Zen 4+).

Fair points, but not everything on Zen 5 is memory-bottlenecked, today. Some things that are already limited would continue to bottleneck on DDR5-7200 (or faster!) with just 16 cores, yet other things still wouldn't be memory-bottlenecked at even 24 cores on DDR5-5600.

Basically, the more memory-bound you become, the lower the value proposition. It doesn't mean the value proposition is zero, because not everything is totally memory-bottlenecked, and for some users with low-bandwidth apps, the value would be quite high.

When AMD launched ThreadRipper Pro, Anandtech investigated the impact of running 64 cores on 4 channels vs. 8 and found that rendering workloads tended not to be much affected by running 16 cores per channel vs. 8. In fact, some gained more performance from the no-Pro's additional clockspeed than they lost from its halving of memory bandwidth!https://www.anandtech.com/show/16805/amd-threadripper-pro-review-an-upgrade-over-regular-threadripper/3
Granted, that's using lower-throughput, lower-clocked Zen 2 cores, but I fully expect the same workloads aren't substantially bandwidth-limited on Zen 5, either.

Also, 3D-VCache should help some of those workloads which are. Now, they just need to give us a 3D cache die on both CCDs!

thestryker said:

Overall moving the 8 core parts to 12 would be a pretty nice MT benefit,

AMD hasn't really mounted a proper response to Raptor Lake's core count increase, IMO. And we're nearing a point where Intel is rumored to be turning the dial up again. Zen 4 and DDR5 really helped, as did Zen 5's dual-decoder architecture, but AMD has lost the big lead it once had in MT performance (i.e. from the Zen 2 and early Zen 3 era) and needs to do more, to stay competitive.

However, I think this really isn't even about desktop, so much as server. We'd do well to keep in mind that most things happening with CCDs are really about server CPUs, with performance desktop & laptops being downstream beneficiaries. I think AMD is really looking to scale up full-fat Zen 6 to 192 cores, and after 4 generations of the 8-core CCD, it's finally time to bump it up to the next step.

thestryker said:

Of course without more PCIe lanes or at least a PCIe 5.0 link to the chipset(s) the productivity improvements brought with higher core counts is still lacking.

I see them as separate issues. Yes, the chipset link should absolutely be PCIe 5.0. I always thought that's the place that made the most sense to upgrade, first. Let's hope Zen 6 will bring that to AM5, just like Zen 2 brought PCIe 4.0 to AM4.