While we’re waiting for the announcement of AMD’s Zen 3 on October 8th, hardware leaker CyberPunkCat has just sent us a preview of the future. AMD processors already occupy five of the six positions on our list of the best gaming CPUs, and Zen 3 is likely to further cement AMD’s position.
The document, which dates back to June 10, appears to have come from AMD’s secret vault. Although the information looks real, we recommend that you proceed with caution. However, the information is consistent with what we already know about the Zen 3 microarchitecture for an AMD accidentally posted presentation.
In this sense, the document is a PPR manual (Processor Programming Reference) for AMD’s Family 19h Model 21h B0. As a refresher, Zen (+) and Zen 2 belong to family 5pm, so family should be 7pm for Zen 3.
No wonder that the processors of the Ryzen 4000 series (code name Vermeer) retain the MCM design (Multi-Chip Module), which is also known as the chiplet design. Zen 3 will package two complex core dies (CCDs) with an I / O chip (IOD) in a chip package. Outwardly, the setup looks identical to Zen 2, but it isn’t. The devil is in the details.
In Zen 2, each CCD contains two core complexes (CCXs), with each complex consisting of four cores that share 16MB of L3 cache. According to the AMD document, the composition of Zen 3 is completely different – there is only one CCX in each CCD. The CCX has eight cores that can be run in either single-thread (1T) or two-thread simultaneous multithreading (2T) mode and contain up to 16 threads per complex. Since there is now only one CCX, all eight CPU cores can now directly access the 32 MB shared L3 cache.
Essentially, the amount of L3 cache at 32MB per CCD in Zen 3 remains the same as in Zen 2. In Zen 2, the four cores in each CCX only have direct access to 16MB of L3 cache, while in Zen 3, all eight cores are present within Zen3 The CCX share the same 32MB L3 cache. The revised design should significantly reduce latency and improve the overall instruction per cycle (IPC) for Zen 3 parts.
In terms of the number of cores, Zen 3 seems to paint a similar picture to Zen 2. The Ryzen 4000 series flagship, possibly the Ryzen 9 4950X, will likely max out at 16 cores and 32 threads, just like the existing Ryzen 9 3950X. With Zen 3, however, you can expect improved clock speeds, as early technical examples of the Ryzen 9 4950X supposedly already climb to 4.9 GHz when the previous Ryzen 9 3950X hits the peak at 4.7 GHz.
According to the information in the document, Zen 3 has two Unified Memory Controllers (UMC), one per channel. Each channel supports up to two DIMMs. The scalable data structure with a capacity of up to 512 GB for each DRAM channel is also mentioned. In terms of memory speed, Zen 3 processors arrive with native support for DDR4-3200, just like Zen 2.