AMD Zen 2 server CPUs feature up to eight octo-core chiplets with central I/O die

Posted on Tuesday, November 06 2018 @ 23:16 CET by Thomas De Maesschalck
AMD logo
The other big news from the AMD Next Horizon event involved the upcoming 7nm Zen 2 based processors. The event focused on the "Rome" EPYC server processors, which are currently sampling with customers. Made on a 7nm process by TSMC, Rome is a multi-chip module that features four to eight CPU dies, with a central 14nm I/O die that handles memory and PCI Express, all linked via InfinityFabric.

The platform will include chips with up to 64 Zen 2 cores, support for 96-lane PCI Express 4.0, and 8-channel DDR4 memory. Other than this, Zen 2 promises an enhanced execution pipeline, an improved branch predictor, better instruction pre-fetching, a re-optimized instruction cache, larger op cache, and floating point enhancements.

AMD didn't reveal how much the IPC has been improved, but word on the street is that you can expect an uplift of up to 15 percent. Combine this with more cores, higher clockspeeds, and better energy efficiency, and you're looking at a mighty rival versus Intel's Xeon lineup.

This is Rome
AMD (NASDAQ: AMD) today demonstrated its total commitment to datacenter computing innovation at its Next Horizon event in San Francisco by detailing its upcoming 7nm compute and graphics product portfolio designed to extend the capabilities of the modern datacenter. During the event, AMD shared new specifics on its upcoming “Zen 2” processor core architecture, detailed its revolutionary chiplet-based x86 CPU design, launched the 7nm AMD Radeon Instinct™ MI60 graphics accelerator and provided the first public demonstration of its next-generation 7nm EPYC™ server processor codenamed “Rome”. Amazon Web Services (AWS), the world’s most comprehensive and broadly adopted cloud platform company, joined AMD at the event to announce the availability of three of its popular instance families on the Amazon Elastic Compute Cloud (EC2) powered by the AMD EPYC™ processor.

“The multi-year investments we have made in our datacenter hardware and software roadmaps are driving growing adoption of our CPUs and GPUs across cloud, enterprise and HPC customers,” said Dr. Lisa Su, president and CEO, AMD. “We are well positioned to accelerate our momentum as we introduce the industry’s broadest, most powerful portfolio of datacenter CPUs and GPUs featuring industry-leading 7nm process technology over the coming quarters.”

AMD Compute Architecture Updates
AMD for the first time detailed its upcoming “Zen 2” high-performance x86 CPU processor core that is the result of a revolutionary modular design methodology. This modular system design uses an enhanced version of AMD Infinity Fabric interconnect to link separate pieces of silicon (“chiplets”) within a single processor package. The multi-chip processor uses 7nm process technology for the “Zen 2” CPU cores that benefit from the advanced process technology, while leveraging a mature 14nm process technology for the input/output portion of the chip. The result is much higher performance – more CPU cores at the same power, and more cost-effective manufacture than traditional monolithic chip designs.

Combining this breakthrough design methodology with the benefits of TSMC’s leading-edge 7nm process technology, “Zen 2” delivers significant performance, power consumption and density generational improvements that can help reduce datacenter operating costs, carbon footprint and cooling requirements. Other key generational advances over the award-winning “Zen” core include:

  • An improved execution pipeline, feeding its compute engines more efficiently.
  • Front-end advances – improved branch predictor, better instruction pre-fetching, re-optimized instruction cache and larger op cache.
  • Floating point enhancements – doubled floating point width to 256-bit and load/store bandwidth, increased dispatch/retire bandwidth and maintained high throughput for all modes.
  • Advanced security features – Hardware-enhanced Spectre mitigations, taking software migration and hardening it into the design, and increased flexibility of memory encryption.
  • Multiple 7nm-based AMD products are now in development, including next-generation AMD EPYC CPUs and AMD Radeon Instinct GPUs, both of which AMD detailed and demonstrated at the event. Additionally, the company shared that its follow-on 7nm+-based “Zen 3” and “Zen 4” x86 core architectures are on-track.

    AMD EPYC Server CPU Updates
    Reinforcing the growing momentum achieved with its current-generation AMD EPYC processors, Matt Garman, vice president of compute services at AWS joined AMD on-stage at the event to announce the immediate availability of the first AMD EPYC processor-based instances on Amazon Elastic Compute Cloud (EC2). Part of AWS’s popular instance families, the new AMD EPYC processor-powered offerings feature industry-leading core density and memory bandwidth. This results in exceptional performance-per-dollar for general purpose and memory-optimized workloads, driven by the core density of AMD EPYC processors that offer M5a and T3a customers a balance of compute, memory, and networking resources for web and application servers, backend servers for enterprise applications, and test/development environments with seamless application migration. For R5a customers, the memory bandwidth advantage of AMD EPYC processors is ideal for in-memory processing, data mining, and dynamic data processing.

    AMD also disclosed new details and delivered performance previews of its next-generation EPYC processors codenamed “Rome”:

  • Processor enhancements including up to 64 “Zen 2” cores, increased instructions-per-cycle1 and leadership compute, I/O and memory bandwidth2.
  • Platform enhancements including the industry’s first PCIe 4.0-capable x86 server processor with double the bandwidth per channel3 to dramatically improve datacenter accelerator performance.
  • Double the compute performance per socket4 and four times the floating point performance per socket5 compared to current AMD EPYC processors.
  • Socket compatibility with today’s AMD EPYC server platforms.
  • AMD demonstrated the performance and platform advantages of its next-generation EPYC processor with two demos during the event:

  • A pre-production single-socket next-generation AMD EPYC processor outperforming a commercially available top-of-the-line Intel dual processor Xeon server running the computationally-intensive, industry standard “C-Ray” benchmark6.
  • The industry’s first x86 PCIe 4.0-capable platform demo, featuring a Radeon Instinct MI60 processor to accelerate image recognition.

    “Rome” is sampling with customers now and is expected to be the world’s first high-performance x86 7nm CPU.


  • About the Author

    Thomas De Maesschalck

    Thomas has been messing with computer since early childhood and firmly believes the Internet is the best thing since sliced bread. Enjoys playing with new tech, is fascinated by science, and passionate about financial markets. When not behind a computer, he can be found with running shoes on or lifting heavy weights in the weight room.



    Loading Comments