❯ Nvidia Reportedly Evaluating Lower VRAM Configurations for Rubin Ultra to Address High-End HBM Shortage

SPEC CUTAccording to multiple supply-chain media reports, Nvidia is evaluating reducing the VRAM configuration of its next-generation flagship GPU, Rubin Ultra, and has been running parallel tests on at least three versions, with some versions falling below previously disclosed specs. The original plan was to use HBM4e 12hi across the entire lineup; now lower-spec options such as HBM4e 8hi, HBM4 12hi, and HBM4 8hi have entered the evaluation sheet.

SUPPLY GAPThe impact is quantifiable: maintaining the top-tier configuration can lift I/O speeds from the previous generation’s 8 to 11.7Gbps up to 14 to 16Gbps; if forced to fall back to lower HBM4 specs, the gain may only reach 11 to 12Gbps. The root of the cut lies in supply — HBM shipment capacity in 2027 is expected to grow 50% to 60% year-on-year, yet still won’t close the gap in AI compute demand, while the most advanced HBM4e 12hi remains uncertain in both validation progress and mass-production yield. This shortage chain has already spilled over to the consumer side: memory-chip price increases are pushing up system costs, and companies like Apple have already raised hardware prices.

CASCADEVRAM cuts do not mean performance is halved — they can be compensated through other means, but the math needs to be redone: AI companies running large models, with smaller per-card VRAM, will need more chips to fit the same model, raising procurement costs per unit of compute. Data center procurement budgets must therefore be rebalanced between “number of cards” and “card specs” — the linear extrapolation based on card count that has been the habit over the past two years no longer holds.

▪ SIGNALEven Nvidia has to make concessions on its own flagship; memory is the true limiting factor in this round of compute expansion.