AMD has announced the next generation of its Epyc server processors [anandtech.com], with up to 64 cores (128 threads) each. Instead of an 8-core "core complex" (CCX) [anandtech.com], AMD's 64-core chips will feature 8 "chiplets" with 8 cores each:
AMD on Tuesday formally announced its next-generation EPYC processor code-named Rome. The new server CPU will feature up to 64 cores featuring the Zen 2 microarchitecture, thus providing at least two times higher performance per socket than existing EPYC chips.
As discussed in a separate story covering AMD's new 'chiplet' design approach [anandtech.com], AMD EPYC 'Rome' processor will carry multiple CPU chiplets manufactured using TSMC's 7 nm fabrication process as well as an I/O die produced at a 14 nm node. As it appears, high-performance 'Rome' processors will use eight CPU chiplets offering 64 x86 cores in total.
Separating CPU chiplets from the I/O die has its advantages because it enables AMD to make the CPU chiplets smaller as physical interfaces (such as DRAM and Infinity Fabric) do not scale that well with shrinks of process technology. Therefore, instead of making CPU chiplets bigger and more expensive to manufacture, AMD decided to incorporate DRAM and some other I/O into a separate chip. Besides lower costs, the added benefit that AMD is going to enjoy with its 7 nm chiplets is ability to easier bin new chips for needed clocks and power, which is something that is hard to estimate in case of servers.
AMD also announced that Zen 4 is under development [anandtech.com]. It could be made on a "5nm" node, although that is speculation. The Zen 3 microarchitecture will be made on TSMC's N7+ process ("7nm" with more extensive use of extreme ultraviolet lithography).
AMD's Epyc CPUs will now be offered on Amazon Web Services [anandtech.com].
AnandTech live blog [anandtech.com] of New Horizon event.
Related: Cray CS500 Supercomputers to Include AMD's Epyc as a Processor Option [soylentnews.org]
Oracle Offers Servers with AMD's Epyc to its Cloud Customers [soylentnews.org]