HBM4 controllers eat ~16% of Nvidia's Rubin die, sparking optical interconnect debate
BenBajarin · x · 2026-10-02
SemiAnalysis estimates HBM4 controllers and PHYs take up roughly 16% of Nvidia's Rubin compute die — a surprising share of leading-edge silicon spent interfacing with memory instead of computing. Ben Bajarin responds that optics could help two ways: moving memory off-die for near-memory HBM, and scale-in optical interconnects that free up the I/O shoreline of the die.
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