Side-by-side specifications of the Synology DS211 and DS211+, from official datasheets. Differences are highlighted.
| DS211 | DS211+ | |
| CPU | 1.6 GHz | 1.6 GHz |
| Cores / threads | 1 core / 1 thread | 1 core / 1 thread |
| RAM (base) | 256 MB | 512 MB |
| RAM (max) | — | 512 MB |
| Drive bays | 2 | 2 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 0 |
| Network | 1× Gigabit Ethernet | 1× Gigabit Ethernet |
| 10GbE | no | no |
| Max raw capacity | 6 TB | 6 TB |
| Hot-swap | no | yes |
| Form factor | desktop | Desktop |
| Released | 2011 | 2010 |
| Power consumption | 22 W / 10.8 W | 24 W / 13 W |
| DSM at launch | — | 3.0 |
Choose the DS211+ if you want the faster Intel CPU and the higher RAM ceiling; that’s the only meaningful performance advantage over the DS211. Neither model offers more than 2 bays or any expansion, and neither has 10GbE or M.2, so if you don’t need the extra CPU/RAM headroom, the DS211 is fine.