The HBM3E used in the MI350 series is believed to be Samsung’s 36GB 12-layer DRAM, completed last year. The chip vertically stacks 24Gb DRAM dies using through-silicon sia (TSV) technology, offering 36GB per package.
SK hynix plans to begin mass production of 12-layer HBM4 chips in the fourth quarter of 2025, supplying initial volumes to Nvidia once Rubin’s launch timeline and order size are confirmed.
