Nvidia de-specced Rubin Ultra HBM from 12-Hi to 8-Hi: $/bandwidth is the bottleneck
AccBalanced · x · 2026-09-06
SemiAnalysis argues Nvidia de-specced Rubin Ultra's HBM from 12-Hi to 8-Hi because the real bottleneck is $/bandwidth, not $/capacity — and walks through the math in a thread.
Related event: SemiAnalysis Explains Why Nvidia Cut Rubin Ultra HBM to 8-Hi(2 posts)→
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