Side-by-side specifications of the Synology DS220j and DS223, from official datasheets. Differences are highlighted.
| DS220j | DS223 | |
| CPU | Realtek RTD1296 | Realtek RTD1619B |
| Cores / threads | 4-core | 4/4 |
| RAM (base) | 512 MB | 2 GB DDR4 non-ECC |
| RAM (max) | 512 MB | 2 GB |
| Drive bays | 2 | 2 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 0 |
| Network | 1x 1GbE | 1x 1GbE |
| 10GbE | no | no |
| Max raw capacity | 32TB | 108 TB |
| Hot-swap | no | yes |
| Form factor | desktop | 2-bay desktop NAS |
| Released | 2020 | 2026 |
Pick the DS223 if you want the better long-term buy: it has a faster dual-core CPU, 2 GB RAM versus the DS220j’s 512 MB, and more headroom for DSM apps and multiple users. Both are 2-bay units with no expansion support, and neither offers 10GbE or M.2. Choose the DS220j only for the cheapest basic file backup box.