HBM3E vs HBM4

HBM3E and HBM4 are two generations of high bandwidth memory, DRAM dies stacked vertically. The main change is interface width. Samsung lists HBM3E with a 1,024-bit organization and HBM4 with 2,048 I/O pins. Per-stack bandwidth is interface width times pin rate, so HBM4 gains from both. HBM3E is also written HBM3e.

Samsung rates HBM3E at up to 9.2 Gb/s per pin and 1,180 GB/s per stack, in 24 GB 8-high and 36 GB 12-high versions. It rates HBM4 at up to 13 Gbps and 3,300 GB/s per 36 GB, 12-high stack. NVIDIA calls the H200 the first GPU with HBM3E, at 141 GB and 4.8 TB/s. The DGX B200 lists eight Blackwell GPUs with 1,440 GB of HBM3e and 64 TB/s, which is 8 TB/s per GPU by division. NVIDIA's HGX page lists the Rubin GPU with 288 GB of HBM4.

The memory type belongs to the GPU, so it is not a separate option. Compare accelerators on capacity per GPU and TB/s, and treat the HBM generation as the tie-breaker. Both are set at purchase and cannot be upgraded.

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Last verified October 30, 2026.