AMD’s Zen 5 architecture is at least a year out, if not further, and yet we have our first bit of news about it from none other than one of the designers of the original Zen platform—legendary microprocessor architect Jim Keller. He recently spoke to college students in Bangalore, India, about the future of processors on behalf of the company he now leads, Tenstorrent. During the talk, he put up a slide comparing all modern data center processors, and amongst the list was a cheeky listing for Zen 5. Does Keller have some inside information? We doubt it, so it’s probably just his best guess as to what AMD might be able to achieve in the future.
In the talk, Keller put up a slide labeled “Scalar Competition Landscape.” It included all modern data center CPUs, including Amazon’s Graviton chips, Intel’s newest Sapphire Rapids CPUs, AMD’s lineage of server CPUs, Nvidia’s Grace chips, and, shockingly, Zen 5. The chart shows their respective performance in SPEC CPU 2017 INT, which, as PCGamer notes, is the industry standard for single-thread integer performance, but not floating point. Keller’s chart is somewhat illuminating in that Zen 5 crushes every other CPU in the lineup, and not by a small margin.
Keller’s slide seems to predict the future. It’s too bad he didn’t include Intel’s Meteor Lake and Arrow Lake on it.
According to Keller’s estimation, Zen 5 is 30% faster than Zen 4, in the form of its current Genoa/Bergamo chips. Since AMD shares chiplets and designs across enterprise and consumer, this is a valid comparison, even though Keller is likely just guessing about Zen 5’s ultimate prowess. It’s also not surprising that a future CPU, built on TSMC’s 3nm process, would be faster than today’s 5nm CPUs. But Keller thinks AMD will be swinging for the fences on the next round.
Keller is a legend in the microprocessor development world and has numerous blockbuster architectures under his belt. He is known for helping AMD develop the K8/Athlon 64 chips and the original Zen architecture. He left AMD for Tesla but was hired by Intel in 2018 to reportedly fix its issues, bringing 10nm to market after numerous delays. He ended up leaving Intel in 2020, citing personal reasons. He also did early work at Apple on its custom A-series SoCs for the iPhone, which were the fastest in the industry, and helped the company develop its own M-series silicon. That is all to say that he knows of what he speaks. It’s a good bet that if he thinks AMD’s Zen 5 will be a barn burner, it’s more likely than not. Sadly, we’ll have to wait until 2024 to find out.