Zen3 architecture question

I’m digging a bit into Zen2/3 atm. Can’t really find a good graphic / schematic on how many CCXs there are for x amount of cores.

So there are always 8x CCX in both desktop and server variants? and depending on the amount of cores total, the amount of active cores in a given CCX is (total core amount / 8)? Meaning an 8 core milan cpu core has the full 32 L3 cache for itself? Seems a bit overkill and pampered.

That would explain all the (gapless) multiples of 8 cores in epyc milan variants. But if I check Ryzen, we got 6 core and 12 core cpus.

Does it work differently for Epyc/Threadripper and Ryzen? Or am I completely wrong?

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There used to be a difference between Desktop parts vs the workstation parts vs the server parts. Desktop Zen2 was 4 cores per CCX. Desktop Zen3 is 8 cores per CCX. TR and Epyc are 8 cores per CCX (and always have been?).

Here are some discussions on the forvm that I found from the search that may help.

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It is a server part. There is no such thing as being pampered. They have divided up their SKUs to target certain markets. If you need high compute, you want as much cache on chip per core as possible.

They have always release released Zen CPUs that were not multiples of 4 and 8. They simply turned off some cores in a CCX. They have even released chips with two CCXes but one CCX was dead. Resulting in a 4 core or 8 core part that consisted of only one active CCX.

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The WIkipedia pages for both EPYC and Ryzen 5000 have a convenient list of core configs for Zen 3 parts, e.g. the EPYC 72F3 is “8x1” which is 8 CCXs each having 1 core enabled (so each core gets the full 32MB L3 cache. They don’t always have an even number of cores active per CCX, e.g. the EPYC 74F3 which is 8x3.

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