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arXiv AI By Satoshi Matsuoka

FP8 is All You Need (Part 2): Full-FP64 3-D FFT on FP8-Generation Tensor CoresThe Integer-Epilogue Wall and the Minimal Hardware That Would Remove It

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The paper presents a design for executing a full‑FP64 1024³ 3‑D FFT on NVIDIA’s Blackwell Ultra (B300) GPU using FP8 tensor cores. It replaces traditional FP64 arithmetic with a sequence of FP8‑tensor DFT GEMMs, Karatsuba‑based residue combination, and exact CRT reconstruction, leaving only a final conversion for rounding. The main bottleneck identified is a per‑output integer epilogue that limits performance to 63–87 ms, far above the theoretical 12.9 ms roof, and the authors propose modest hardware changes—such as an INT8 tensor core and cross‑column accumulation—to reduce this gap.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv AI.

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