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GuideGlossaryHBM4

HBM4

The next high-bandwidth-memory generation with wider interfaces and a logic base die, targeting late-2020s accelerators.

Current numbers

H100 80GB → Rubin Ultra 1TBper-GPU usable HBM capacity trajectory (H100 80GB, B200 SXM 180GB, B300 SXM 288GB, Rubin 288GB HBM4, Rubin Ultra announced at 1TB)as of 2026-08 (roadmap in flux) · register ↗
~288 GBHBM4 per Rubin GPU at ~22 TB/s; trajectory H100 80 GB → H200 141 GB → B200 180 GB → B300 288 GB → Rubin Ultra 1 TBas of 2026-07 · register ↗
~288 GBHBM4 capacity per Rubin-class package at ~2.75 TB/s/stack (~22 TB/s per package) — the memory the package area enablesas of 2026-07 · register ↗

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