Side-by-side specifications of the Synology DS423 and DS423+, from official datasheets. Differences are highlighted.
| DS423 | DS423+ | |
| CPU | Realtek RTD1619B | Intel Celeron J4125 |
| Cores / threads | 4/4 | 4 |
| RAM (base) | 2 GB DDR4 | 2 GB |
| RAM (max) | 2 GB | 6 GB |
| Drive bays | 4 | 4 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 2 |
| Network | 2x 1GbE RJ-45 | 2 x 1GbE RJ-45 |
| 10GbE | no | no |
| Max raw capacity | 108 TB | 108 TB |
| Hot-swap | yes | yes |
| Form factor | Desktop | Desktop |
| Released | 2026 | 2023 |
Pick the DS423+ if you want the stronger Intel CPU, upgradeable RAM, and M.2 NVMe slots; it’s the better choice for apps, Plex, and heavier SMB use. Pick the DS423 if you just need basic file storage and backups: it has a weaker CPU, fixed RAM, no M.2, no 10GbE, and neither model expands beyond 4 bays.