Side-by-side specifications of the Synology RS812 and RS812+, from official datasheets. Differences are highlighted.
| RS812 | RS812+ | |
| CPU | Intel Atom Dual Core 2.13 GHz | Intel Atom Dual Core 2.13 GHz |
| Cores / threads | 2 cores / 2 threads | 2 cores / 2 threads |
| RAM (base) | 1 GB DDR3 | 1 GB DDR3 |
| RAM (max) | 3 GB | 3 GB |
| Drive bays | 4 | 4 |
| Expandable to | 4 via RX410 | 4 via RX410 |
| M.2 slots | 0 | 0 |
| Network | 2x Gigabit | 2x Gigabit |
| 10GbE | no | no |
| Max raw capacity | 24 TB with RX410 | 24 TB with RX410 |
| Hot-swap | yes | yes |
| Form factor | 1U rackmount | 1U rackmount |
| Released | 2012 | — |
| Power consumption | 37 W / unknown | 46.2 W / null |
| DSM at launch | — | — |
Choose the RS812+ if you want materially better headroom: it has a faster CPU, higher RAM ceiling, and can use 10GbE expansion; the RS812 is the lower-end model. Both are 2-bay units with no M.2 support and no built-in expansion beyond the two bays, so for a simple 2-bay file server the RS812 is the cheaper pick.