Graphcore Bow IPU

The Bow IPU, announced in March 2022, was the first processor in volume production built with wafer-on-wafer 3D stacking. Graphcore bonded a second wafer under the compute die whose only job is power delivery, putting deep trench capacitors directly beneath the logic they feed, and the cleaner supply let the same Colossus MK2 design clock at 1.85 GHz instead of 1.325. Nothing else changed: 1,472 IPU-Cores, 8,832 threads and 900 MB of In-Processor Memory, architecturally compatible with the GC200 so that existing code runs unmodified. The result is 350 TFLOPS of FP16.16 against the GC200's 250, on-chip bandwidth up from 45 to 65 TB/s, and Graphcore's claim of up to 40 percent more real-world performance and 16 percent better efficiency. Like the GC200 it has no DRAM and no card SKU: it ships four to a 1U Bow-2000 IPU-Machine, and those stack into Bow Pod systems of up to 256.