Fujitsu shows off its Armv9-based 144-core mechanical sample Monaca processor For the data center, some details were revealed. Less than a week ago, it revealed that it was developing it in partnership with Broadcom and relied on its 3.5D extreme size system packaging platform. The image was released by Satoshi Matsuoka, director of the RIKEN Center for Computational Science (R-CCS) and professor at Tokyo Institute of Technology.
Fujitsu’s Monaka is a giant CoWoS system-in-package (SiP) that features four 36-core computing dies built on TSMC’s N2 process technology, housing 144 Armv9-based cores, with these enhancements stacked face-to-face on blocks of SRAM of the top. The SRAM blocks (essentially giant caches) are produced using TSMC’s N5 process technology. The compute and cache stack features a relatively large I/O die that incorporates a memory controller, PCIe 6.0 lanes, and CXL 3.0 on top for connecting accelerators and expanders, as well as other interfaces expected from a data center-class CPU .
As expected, Monaka targets a wide range of data center workloads and does not rely on high-bandwidth memory, but will use mainstream DDR5 DRAM, possibly in its MR-DIMM and MCR-DIMM Implemented to provide adequate capacity and achieve data center processor costs.
Fujitsu’s Monaka processor will use a core built on the Armv9-A instruction set architecture and incorporate Scalable Vector Extensions 2 (SVE2). Fujitsu has not specified a fixed vector length for this design, which ranges from 128 to 2048 bits. Since the A64FX supports vectors up to 512 bits, the Monaka processor may support vectors of similar or larger sizes. Monaka will use advanced Safety Features, including Armv9-A’s Confidential Computing Architecture (CCA), provide enhanced workload isolation and robust protection.
Monaka will compete with AMD’s EPYC and Intel’s Xeon processors, so it must offer an undisputed advantage. That advantage could be energy efficiency, as Fujitsu aims to double its efficiency compared to competitors by 2026-2027 when relying on air cooling. Since Monaka is an Arm-based CPU, it is more energy efficient than x86 processors.
Fujitsu’s Monaka processors for data centers will be available in fiscal 2027, which starts on April 1, 2026, and ends on March 31, 2027.