During the last Financial Analyst Day, AMD reiterated that this year we will see the arrival on the market of based processors Zen architecture 3. Probably we will start from the server (EPYC third generation Milan) and desktop (Ryzen 4000 Vermeer) sectors, and then proceed in the first part of 2021 with the solutions for the workstations (Ryzen Threadripper Genesis Peak).
AMD has so far kept its mouth sewn on the characteristics of the new architecture, implying that it will be a important renewal of what we have seen with Zen 2. The only thing certain that the production of the Zen 3 CPUs will be done by TSMC with a 7 nanometer production process improved compared to the current one, which should guarantee a further step forward in the relationship between performance and consumption. It is rumored that the TDP of future CPUs will remain identical or very similar to that of current models.
Click to enlarge
On the web, rumors are running fast and some chatter about the potential of Zen 3 circulated in recent weeks. Needless to say, you have to take it all with pliers, but there are some voices that are re-proposing themselves and therefore acquire a slightly greater weight. The Youtube channels RedGamingTech and AdoredTV both report that Zen 3 architecture will offer improved IPC performanceso with single-threaded loads, 10 to 15%. Significant progress, to which higher clock frequencies would be added – there is talk of 50-100 MHz for Ryzen and up to 200 MHz for EPYC.
Multi-threading performance could go up even more, thanks to higher boost frequencies with more cores under load and architectural innovations. According to a slide circulated in recent months, in fact, we will see unification of the L3 cache of the CCX.
Click to enlarge
The current Zen 2 processors are based on a CCX with 4 cores, each equipped with its own L3 cache (16 MB), coupled with a second CCX to form an 8-core chiplet. With Zen 3, the CCX should become "all in one piece", guaranteeing 8 cores and precisely a unified L3 cache. A quantitative increase in the L3 cache cannot be excluded, with the transition from 32 MB to 48/64 MB. The new configuration should ensure a reduction in latency compared to the current design. Still on the subject of cache, there is a rumor performance increase of L1 cache up to 40%.
As for the number of cores, at the moment there does not seem to be an increase on the horizon, but not to be excluded a priori. Architecture should continue to guarantee a Simultaneous Multi-Threading "Classic", which is two logical threads per core. There has been rumors of a possible move to SMT4, with four threads per core, but the indiscretion seems to be denied by a slide leaked during an AMD presentation at the HPC-AI Advisory Council UK conference. The architecture should also continue to support AVX-256 instructions.
Click to enlarge
As for platforms, although we will probably witness the arrival of a new chipset like the X670, Zen 3 processors should continue to be compatible with current motherboards and sockets, offering support for PCI Express 4.0 and DDR4 memories.
AdoredTV – which does not have a good reputation after some rumors about Ryzen 3000 – has also stated that it has gotten some indiscretions about Zen 4, architecture planned for 2021 made with production process a 5 nanometers: in addition to the foreseeable need for a new socket (apparently DDR5 and PCIe 5.0 supporter), there is talk of a greater number of cores, 1 MB of L2 cache, AVX-512 support and a further improvement of the IPC.
