HBM2
Graphics Cards · 4 specs
Direct Answer
HBM2, standardized by JEDEC in January 2016, doubled HBM's maximum stack height to 8 dies and its per-pin transfer rate, reaching up to 256 GB/s of bandwidth per stack and 8GB of capacity per package.
Source: JEDEC JESD235a · Last reviewed Aug 28, 2026
Specs
| JEDEC Standard | January 2016 (JESD235a) |
| Max Dies Per Stack | 8 |
| Max Bandwidth / Data Rate | 256 GB/s per stack |
| Available Capacity Range | 8GB per package |
More Dies, More Bandwidth
JEDEC standardized HBM2 as JESD235a in January 2016, extending the original HBM spec to support stacks of up to 8 dies (versus HBM1's lower maximum) and doubling the pin transfer rate to up to 2 GT/s, together pushing maximum bandwidth to 256 GB/s per stack and capacity to 8GB per package. A later unofficial industry extension, commonly called HBM2E and specified by JEDEC in late 2018, pushed further still, to roughly 307 GB/s per stack with 12-die, 24GB stacks.
HBM2 has appeared in a range of high-end GPUs and compute accelerators since its introduction, continuing HBM's positioning as a high-bandwidth, high-cost option reserved for products where that tradeoff makes sense, rather than mainstream consumer graphics cards.