Side-by-side specifications of the Synology RS814 and RS815RP+, from official datasheets. Differences are highlighted.
| RS814 | RS815RP+ | |
| CPU | Intel Atom Dual Core 2.13GHz | Intel Atom C2538 |
| Cores / threads | 2 | 4c/4t |
| RAM (base) | 1GB | 2 GB |
| RAM (max) | 4GB | 6 GB |
| Drive bays | 4 | 4 |
| Expandable to | 4 | 8 |
| M.2 slots | 0 | 0 |
| Network | 2x Gigabit | 4x Gigabit |
| 10GbE | no | no |
| Max raw capacity | 16TB | 24 TB |
| Hot-swap | yes | yes |
| Form factor | 1U rackmount | 1U rackmount |
| Released | 2013 | 2015 |
Choose the RS815RP+ if you want the better platform: it has a much faster Intel Atom C2538 CPU, 2 GB RAM with a higher ceiling (up to 6 GB), and built-in redundant power supplies. It also has 4 bays like the RS814, but the RS815RP+ is the stronger choice for heavier SMB workloads; neither model has 10GbE or M.2, and expansion is via Synology expansion units rather than onboard M.2 storage.