Side-by-side specifications of the Synology RS3621XS+ and SA6400, from official datasheets. Differences are highlighted.
| RS3621XS+ | SA6400 | |
| CPU | Intel Xeon D-1541 | AMD EPYC 7272 |
| Cores / threads | 8/16 | 12/24 |
| RAM (base) | 8 GB | 32 GB |
| RAM (max) | 64 GB | 1024 GB |
| Drive bays | 12 | 12 |
| Expandable to | 36 | 108 |
| M.2 slots | 2 | 0 |
| Network | 4x 1GbE/10GbE RJ-45 | 4x 1GbE, 2x 10GbE |
| 10GbE | yes | yes |
| Max raw capacity | 1 PB | 1.944 PB |
| Hot-swap | yes | yes |
| Form factor | 2U | 2U rackmount |
| Released | 2025 | 2025 |