AMD MI455X peak HBM4 memory bandwidth per accelerator
23.3 TB/sobserved
| Value kind | observed — Reported measurements, counts, and specifications keep the precision and scope stated by their source; an exact specification is not treated as a range. |
|---|---|
| Scope | Vendor peak for one MI455X (12 HBM4 stacks, 432 GB). The Helios rack spec table gives the same 23.3 TB/s per GPU; AMD's 2025 Helios preview, and one compute-tray description still on the Helios page, give 19.6 TB/s. A delivered OEM configuration may list a different value. |
| Caveat | AMD's comparison panel sets this against Vera Rubin's announced 22 TB/s; NVIDIA's shipping specification is 19.2 TB/s per GPU. |
| As of | 2026-10 |
| Source | AMD Instinct MI455X product page (read 2026-10-19); the same figure appears in AMD's Hot Chips 2026 MI400 talk (2026-08-24). · GPU Memory: Stacks of Memory 12; Peak Memory Bandwidth 23.3 TB/s. |
| Review | checking…review by 2027-01-15 · standard cadence |
| Recorded changes | last 2026-10-19 |
| Claim id | mi455x-hbm4-peak-bandwidth-23-3-tb-s |
Where the guide uses it
Not quoted in a chapter yet; it is kept in the curated register.
← Full numbers register — every date-stamped figure in the guide, with revision history.