Graphcore Bow IPU
The wafer-on-wafer pioneer whose company became SoftBank's AI chip arm.
You're looking at a chip record: what this processor is, its key specs, who designs, manufactures and supplies its parts, and where it gets used.
Graphcore's Bow IPU was the first production chip to use wafer-on-wafer 3D stacking (with TSMC), putting a power-delivery die under the compute die. The IPU's 1,472 cores and on-chip SRAM anticipated later designs, but the company missed the LLM wave commercially and was acquired by SoftBank in 2024 — its team now builds AI silicon inside the SoftBank/Arm orbit.
Specifications & key facts
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Overview
Manufacturing
Memory
Compute
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Sources
Record reviewed as of 2026-01-15 — see Methodology.