Side-by-side specifications of the Synology DS1815+ and DS3615xs, from official datasheets. Differences are highlighted.
| DS1815+ | DS3615xs | |
| CPU | Intel Atom C2538 | Intel Core i3-4130 3.4GHz |
| Cores / threads | 4 cores / 4 threads | 2 cores / 4 threads |
| RAM (base) | 2 GB DDR3 | 4GB DDR3 ECC |
| RAM (max) | 6 GB | 32GB |
| Drive bays | 8 | 12 |
| Expandable to | 10 (DX513; 18 total) | 24 |
| M.2 slots | 0 | 0 |
| Network | 4x Gigabit Ethernet | 4 x Gigabit |
| 10GbE | no | optional |
| Max raw capacity | 48 TB internal; 108 TB with DX513 expansion | 216TB |
| Hot-swap | yes | yes |
| Form factor | Tower | Tower |
| Released | 2014 | 2015 |
| Power consumption | — | — |
| DSM at launch | — | — |