Side-by-side specifications of the Synology RS1619xs+ and RS1626xs+, from official datasheets. Differences are highlighted.
| RS1619xs+ | RS1626xs+ | |
| CPU | Intel Xeon D-1527 | Intel Xeon D-1726 |
| Cores / threads | 4 cores / 8 threads | 6 cores / 12 threads |
| RAM (base) | 8 GB DDR4 ECC UDIMM | 16 GB DDR4 ECC RDIMM |
| RAM (max) | 64 GB | 64 GB |
| Drive bays | 4 | 4 |
| Expandable to | 16 total with RX1217/RX1217RP | 16 total with RX1225RP |
| M.2 slots | 2 M.2 2280 NVMe/SATA | 2 NVMe |
| Network | 4 × 1GbE RJ-45 | 2 x 10GbE RJ-45; 1 x out-of-band management LAN |
| 10GbE | optional | yes |
| Max raw capacity | 192 TB | Unknown |
| Hot-swap | yes | yes |
| Form factor | 1U rackmount | 1U rackmount |
| Released | 2019 | 2026 |
| Power consumption | 68.68 W / 34.78 W | 97.59 W / 56.19 W |
| DSM at launch | — | — |
Choose the RS1626xs+ if you want the newer, clearly more capable platform: it has a faster CPU, higher RAM ceiling, more drive bays/expansion headroom, built-in 10GbE, and M.2 slots. The RS1619XS+ is the older, lighter option, so pick it only if lower cost matters more than future-proofing and expansion.