Side-by-side specifications of the Synology DS211j and DS211+, from official datasheets. Differences are highlighted.
| DS211j | DS211+ | |
| CPU | Marvell 88F6281 | 1.6 GHz |
| Cores / threads | 1/1 | 1 core / 1 thread |
| RAM (base) | 128 MB | 512 MB |
| RAM (max) | 128 MB | 512 MB |
| Drive bays | 2 | 2 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 0 |
| Network | 1x Gigabit Ethernet | 1× Gigabit Ethernet |
| 10GbE | no | no |
| Max raw capacity | 6 TB | 6 TB |
| Hot-swap | no | yes |
| Form factor | Desktop | Desktop |
| Released | 2010 | 2010 |
| Power consumption | 28.2 W / 9.5 W | 24 W / 13 W |
| DSM at launch | — | 3.0 |
Pick the DS211+ if you want the faster CPU and more RAM headroom; the DS211J is the slower, lower-end model and is the better choice only if you just need basic file storage. Both are 2-bay units with no expansion, and neither has 10GbE or M.2.