Side-by-side specifications of the Synology RS3618xs and RS3626xs, from official datasheets. Differences are highlighted.
| RS3618xs | RS3626xs | |
| CPU | Intel Xeon D-1521 | Intel Xeon D-1726 |
| Cores / threads | 4 cores / 8 threads | 6 cores / 12 threads |
| RAM (base) | 8 GB DDR4 ECC UDIMM | 8 GB DDR4 ECC UDIMM |
| RAM (max) | 64 GB | 48 GB |
| Drive bays | 12 | 12 |
| Expandable to | 36 total with 2 expansion units | 36 |
| M.2 slots | 0 | 0 built-in; optional via adapter card |
| Network | 4 × 1GbE RJ-45 | 2× 10GbE RJ-45, 1× out-of-band management LAN |
| 10GbE | optional | yes |
| Max raw capacity | 216 TB | 36 drives |
| Hot-swap | yes | yes |
| Form factor | 2U rackmount | 2U rackmount |
| Released | 2018 | 2026 |
| Power consumption | 142.76 W / 55.05 W | 147.79 W / 75.73 W |
| DSM at launch | — | — |