Side-by-side specifications of the Synology DS212J and DS212+, from official datasheets. Differences are highlighted.
| DS212J | DS212+ | |
| CPU | Marvell 6281 | unknown |
| Cores / threads | 1/1 | unknown |
| RAM (base) | 256MB | 512MB |
| RAM (max) | 256MB | 512MB |
| Drive bays | 2 | 2 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 0 |
| Network | 1x Gigabit | 1x Gigabit |
| 10GbE | no | no |
| Max raw capacity | 6TB | 6TB |
| Hot-swap | no | yes |
| Form factor | desktop | desktop |
| Released | 2011 | 2012 |
Choose the DS212+ if you want the faster CPU and more headroom: it has the better processor, supports up to 512 MB RAM, and is the stronger pick for heavier SMB use. Both are 2-bay units with no expansion, no 10GbE, and no M.2, so the real decision is performance versus budget; the DS212J is the lighter home option.