What just happened? During the ActivateNow: Technology Summit held at the Computer History Museum in California last week, a Fujitsu representative off-offhandedly mentioned an upcoming Arm-based CPU slated for 2027 that caught the attention of some in the audience. The Register pressed the company for more details and learned it was developing a successor to the A64FX codenamed Monaka.

Fujitsu launched its first Arm-based high-performance compute (HPC) CPU in 2019. The bluntly-named A64FX has 48 processor cores clocked around 2GHz and four additional assistant cores. It has 32 GB of onboard HBM2 and many more HPC features including 512-bit scalable vector extensions (SVEs). Almost 160,000 A64FXs power the Fugaku supercomputer, which was the fastest supercomputer in the world from 2020 to 2022 when it was succeeded by the Epyc-powered Frontier.

Monaka "will have a wider range of features and will prove more energy efficient" than the A64FX, a spokesperson told The Register. "The range of potential applications is wider than that of the A64FX, which has special characteristics (eg, interconnects) specific to Fugaku." Some of those characteristics include the Tofu interconnect D fabric and the limit of 32 GB of memory, which can't be expanded.

Energy efficiency is a priority in the design of Monaka. Fujitsu emphasizes its "overwhelming energy efficiency" that will "contribute to the realization of a carbon-neutral and sustainable society" in its materials. The company hopes that the CPU will be at least 70 percent faster than its competitors in AI and HPC workloads while being twice as efficient.

Japan's New Energy and Industrial Technology Development Organisation (NEDO) is encouraging and supporting Fujitsu in its endeavors to create more energy-efficient processors as part of its plan to reduce the energy consumption of data centers in Japan by 40 percent by 2030. As part of the initiative, Fujitsu is also contributing to the co-development of other energy-efficient technologies, including low-power accelerators and photonics-based network interface controllers (NICs).

Arm-based processors are proving to be a popular pick in countries that incentivize sustainability. Arm processors are intrinsically more efficient than x86 alternatives, with Amazon, Google, and Nvidia all investing in their application to HPC workloads right now.