# Fujitsu details MONAKA at Hot Chips: 144 Arm cores on 2nm dies stacked over 5nm cache, samples shipping

Canonical page: https://technooptimist.io/stories/fujitsu-details-monaka-at-hot-chips-144-arm-cores-on-2nm-dies-stacked-808c4cc4
Date: 24 Aug 2026
About: [Fujitsu](https://technooptimist.io/companies/fujitsu.md) · [FUJITSU-MONAKA](https://technooptimist.io/computing/monaka.md)
Original source: https://xenospectrum.com/en/fujitsu-monaka-stacked-chiplet/

At Hot Chips 2026 Fujitsu laid out MONAKA's design: four 36-core dies on TSMC's 2nm N2P bonded onto 5nm SRAM dies, with a 5nm I/O die in the centre. Evaluation samples are shipping and mass production is planned for 2027. Fujitsu also gave performance estimates, without full test conditions.

## Key facts

- Two versions: 2.1 GHz at 350 W air-cooled and 2.9 GHz at 500 W liquid-cooled.
- 12-channel DDR5 above 8,000 MT/s and 96 lanes of PCIe 6.0 / CXL 3.0.
- Estimated 69.7–96.2 INT8 TOPS for AI inference and about 500 GB/s memory bandwidth.
- 2nm silicon is under 30% of the chip's total area; all last-level cache sits on the 5nm dies.
- Successor MONAKA-X, on 1.4nm for 2029, is to be the CPU of FugakuNEXT.

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