Side-by-side specifications of the Synology RS818RP+ and RS820RP+, from official datasheets. Differences are highlighted.
| RS818RP+ | RS820RP+ | |
| CPU | Intel Atom C2538 | Intel Atom C3538 |
| Cores / threads | 4-core | 4-core |
| RAM (base) | 2 GB | 2 GB DDR4 |
| RAM (max) | 16 GB | 18 GB |
| Drive bays | 4 | 4 |
| Expandable to | 8 | 8 |
| M.2 slots | 0 | 0 |
| Network | 4 x 1GbE | 4x 1GbE |
| 10GbE | optional | optional |
| Max raw capacity | 80 TB | 88 TB |
| Hot-swap | yes | yes |
| Form factor | 1U | 1U rackmount |
| Released | 2018 | 2022 |