Side-by-side specifications of the Synology DS1817 and DS1817+, from official datasheets. Differences are highlighted.
| DS1817 | DS1817+ | |
| CPU | Intel Atom C2538 1.7 GHz | Intel Atom C2538 2.4GHz |
| Cores / threads | quad-core/4 threads | 4 cores / 4 threads |
| RAM (base) | 4 GB | 2 GB DDR3 SO-DIMM |
| RAM (max) | 8 GB | 16 GB |
| Drive bays | 8 | 8 |
| Expandable to | 10 | 10 (2 DX517 units) |
| M.2 slots | 0 | 2 via optional M2D17 adapter |
| Network | 2 x 1GbE RJ-45, 2 x 10GBASE-T RJ-45 | 4 x 1GbE RJ-45 |
| 10GbE | yes | optional |
| Max raw capacity | 180 TB | 108 TB |
| Hot-swap | yes | yes |
| Form factor | desktop | Desktop |
| Released | 2017 | 2017 |
| Power consumption | — | — |
| DSM at launch | — | — |
Choose the DS1817+ if you want the stronger CPU, higher RAM ceiling, and better cache options: it uses a faster Intel CPU, supports up to 8GB RAM officially, and adds M.2 NVMe slots for SSD cache. Both have 8 bays and can expand to 18 drives with Synology expansion units, and both support optional 10GbE via an add-in card. Pick the DS1817 only if you want the cheaper unit and don’t need the faster CPU or M.2 cache.