AMD says the Zen 3 core will be “an entirely new architecture.” That’s according to AMD’s Forest Norrod who’s been telling The Street that Zen 2 “was more of an evolution of the Zen microarchitecture that powers first-gen EPYC CPUs – Zen 3 will be based on a completely new architecture.”
Most of us were pretty impressed with the Zen 2 layout, shipping the Zen cores onto discrete 7nm chiplets with a 12nm IO die sitting in the middle of it all. So much so that it rules the roost in our list of the best CPUs for gaming.
That architectural move allowed AMD to shift to the advanced 7nm node without relying on the new production lithography being mature enough to produce large monolithic processors. The smaller chiplets and mature 12nm IO dies meant yields were far higher than AMD would have otherwise gotten from a traditional design on 7nm. So it feels a little bit like Norrod’s downplaying the revolutionary nature of the latest Ryzen and EPYC processor designs.
But, to be fair to ol’ Forest, the actual microarchitecture inside was very much an evolution of the original Zen core design, Zen 2 just allowed for more of those cores to be jammed into the same package.
You can read the piece on The Street (via WCCFTech) where Norrod suggests that in terms of IPC alone Zen 3 will deliver performance gains over Zen 2 “right in line with what you would expect from an entirely new architecture.”
Zen 2 delivered a 15% IPC bump, which he admits was bigger than you’d normally get from an “evolutionary upgrade” but that does suggest the speed hike from Zen 3 could end up being well north of even that. Which would be pretty spectacular.
AMD’s Mark Papermaster had tempered expectations for Zen 3, but recently rumours had been suggesting a far more enticing IPC improvement from the new chips.
Right now Intel still just about has the IPC lead over AMD, with the red team able to offer a better-value part thanks to its still-competitive performance and abundance of cores. If Zen 3 can push past Intel’s IPC level then it will be completely untouchable when it launches the new 7nm+ chips next year.
Norrod also goes on to say that AMD had appropriated Intel’s tick-tock CPU design cadence, something we suggested a little while back, where a new lithography would come with an existing microarchitecture as a ‘tick’ and a new architecture would follow on a similar production node as a ‘tock’.
That makes 7nm Zen 2 a ‘tick’ and the upcoming 7nm+ Zen 3 a ‘tock’ – following that you’d expect a 5nm Zen 4 ‘tick’, potentially on a new processor socket, and a Zen 5 ‘tock’.