Unlike the previous generation design where each CCD comprised of two CCX's (Core Complexes), the Zen 3 CCD will consist of a single CCX which will feature 8 cores that can run in either a single-thread mode (1T) or a two-thread mode (2T) for up to 16 threads per CCX. Since the chip houses a maximum of two CCDs, the core and thread count will max out at 16 cores and 32 threads which is the same as the existing flagship AM4 desktop CPU, the Ryzen 9 3950X.

Each Zen 3 core will feature 512 KB of L2 cache for a total of 4 MB of L2 cache per CCD. That should equal 8 MB of L2 cache on a dual CCD CPU. Along with the L2 cache, each CCD will also comprise of up to 32 MB of shared L3 cache. For Zen 2, the L3 cache was split between the two CCX's with each CCX having their own separate (Up To) 16 MB cache. The size of the cache remains the same per CCD but now all cores can share a larger number of L3 cache.

https://wccftech.com/amd-zen-3-ryzen-4000-vermeer-cpus-detailed-up-to-16-cores-32-threads/

New rumors

• CPUs will have 5xxx names
• It won't be 16 core CPUs (12 cores tops), at least in retail and at initial stages
• AMD can't make too much fully non defective 8 core chiplets now
• Main issue can be horrible situation with 7nm EUV process on TSMC
• AMD had been forced to use this process as 5nm capacity is literally not available

Note that for Zen 2 and Zen 1 number of total fully nondefective chiplets reached 98% after few months, so almost all of lower end CPUs have intentionally disabled cores and even most of the nonconnected chiplets in Threadrippers had been fully functional.

AMD can repeat stunt they made with client IO die (part of processor that deal with IO and RAM)

X570 chipset had been actually just mostly rewired IO die from Zen 2 CPU.

X670 chipset can be again just die put on separate board.

AMD Ryzen 9 5900X

• 12 cores only
• IPC improvement of up to 20% (around 3% in real life)
• Boost clocks (for short periods) of up to 5 GHz (+300 MHz improvement over the Ryzen 9 3900XT)
• CPU won't be able to offer much higher sustainable all core clock
• 150W TDP (not real consumption, just spec)
• Real consumption will pass 200w for heavy loads during boosts time or overclock
• Price will jump around 15-20% compared to 3900XT

Can be fake, but...

AMD Epyc Milan, Zen 3 based

Some slides

UK prices

• Ryzen 9 5950X - 750 GBP
• Ryzen 9 5900X - 530 GBP
• Ryzen 7 5800X - 430 GBP
• Ryzen 5 5600X - 290 GBP

EU prices

• Ryzen 9 5950X - 830-850 EUR
• Ryzen 9 5900X - 570-580 EUR
• Ryzen 7 5800X - 470-480 EUR
• Ryzen 5 5600X - 313-320 EUR

Note that AMD also excluded coolers from all but cheapest 6 core models, so profits (including saving on cooler and price rise) are around $100 bigger for most models now.

On BIOS updates

Taiwan manufacturers current plans

• Most X570 and B550 boards will get updates
• Most X470 board won't get updates
• Almost all B450 board won't get updates
• Almost none or totally none of X350 and B350 (totally marketing decision)

On memory

Some new benchmarks