Side-by-side specifications of the Synology DS411j and DS411+, from official datasheets. Differences are highlighted.
| DS411j | DS411+ | |
| CPU | 1.2GHz | Intel Atom D510 |
| Cores / threads | — | 2C/2T |
| RAM (base) | — | 1 GB DDR2 |
| RAM (max) | — | 1 GB |
| Drive bays | 4 | 4 |
| Expandable to | — | — |
| M.2 slots | 0 | 0 |
| Network | 1x Gigabit | 1x Gigabit |
| 10GbE | no | no |
| Max raw capacity | 12TB | 16 TB |
| Hot-swap | no | yes |
| Form factor | desktop | desktop |
| Released | 2010 | 2010 |
Choose the DS411+ if you want the better CPU and more RAM headroom; it’s the only one that’s meaningfully faster for heavier file serving and multiple users. Both are 4-bay units with no expansion support, and neither has 10GbE or M.2, so the real decision is performance and memory: DS411+ over DS411j.