AMD Zen 3 Vermeer to include 12-core Ryzen 9 5900X and 8-core Ryzen 7 5800X; rumored to focus on boost sustainability over peak speeds
The upcoming AMD Zen 3 Vermeer family will apparently include the Ryzen 9 5900X (12 cores) and the Ryzen 7 5800X (8 cores), according to a tweet by Patrick Schur who has been fairly consistent with AMD-related leaks in the past. Though somewhat on anticipated lines, it does reaffirm that AMD would indeed be aligning the upcoming Cezanne (Renoir successor) and Vermeer nomenclatures under a common Ryzen 5000 series as was speculated earlier.
The tweet isn't entirely revelatory in itself, but it looks like Zen 3 will continue to offer similar core/thread counts as Zen 2 Matisse. So, while the 5900X will be the probable flagship CPU, a 5950X with a 16C/32T configuration is likely to be in the offing as well.
Schur also confirms that previous OPNs reported by Igor's Lab were, in fact, 12C parts and not 16C as was originally thought. Whether there would be 10C/20T parts this time around is still anybody's guess — a 5850X, anyone?.
AMD Zen 3 - New CCX design and overclocking features
Meanwhile, Videocardz's source has offered some hints on the new features that can be expected in Zen 3. Quoting the source verbatim,
- Zen3 will be the first major redesign of Zen, focusing on performance/watt and scalability.
- Better IPC, 8 core per CCX, new IO chip with better memory controller, improved SMT, and more efficient boost.
- The new boost is not focusing on getting much higher clocks, it is designed to manage long workloads, it can be sustained for several minutes.
These are pretty interesting points. We've previously reported that Zen 3 will usher-in a new CCX design. Zen 2's CCX housed four cores with with 16 MB L3 cache per CCX. In Zen 3, each CCX will house eight cores and a common 32 MB L3 cache. Whether there would be higher cache capacities per CCX is not yet known. The previous CCX design still allowed for cross-CCX cache access (at a slight performance penalty), but the newer common 32 MB L3 cache for all eight cores should have a sizeable impact in minimizing latency.
Zen 3 will offer improved IPC over Zen 2. While that is a given, exactly how much is still a matter of speculation. All indications so far point to anywhere between a 10-15% IPC increase per thread, which is still good considering the fact that Zen 3 is an optimization phase (of the inflection-optimization cycle) of the 7 nm node.
The final point about boost is new information. Previously, we reported based on available OPN codes from Igor's Lab that there is a possibility of Zen 3 finally hitting 5 GHz boost. Although the current information does not directly refute that, it looks like the clock speed increases will be rather conservative or just short of 5 GHz. Instead, AMD may focus on providing for a longer sustained boost. It is still early days to speculate, but if this leak is indeed true, then our expectations with respect to insane clocks might have to be tempered.
Apart from these features, Zen 3 is also expected to offer per-core overclocking control and new Infinity Fabric (IF) dividers that allow setting the memory controller frequency (UCLK) a bit higher than the IF frequency (FCLK). Previously, de-syncing the FCLK and DRAM frequency (MEMCLK) would result in UCLK=1/2 MEMCLK leading to higher latency. Possibly, the "new IO die with better memory controller" being alluded to refers to this new functionality.
The Zen 3 lineup will be officially announced on October 8.
Look, what I've found! ????— Patrick Schur (@patrickschur_) September 16, 2020
AMD Ryzen 9 5900X (12 Core)
AMD Ryzen 7 5800X (8 Core)