Side-by-side specifications of the Synology DS210j and DS211, from official datasheets. Differences are highlighted.
| DS210j | DS211 | |
| CPU | 800 MHz | 1.6 GHz |
| Cores / threads | 1 core / 1 thread | 1 core / 1 thread |
| RAM (base) | 128 MB | 256 MB |
| RAM (max) | — | — |
| 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 | 4 TB | 6 TB |
| Hot-swap | no | no |
| Form factor | Desktop | desktop |
| Released | 2009 | 2011 |
| Power consumption | 25 W / 10 W | 22 W / 10.8 W |
| DSM at launch | 2.2 | — |
Choose the DS211: it has a much faster 1.6 GHz Marvell Kirkwood CPU and 256 MB RAM versus the DS210j’s 1.2 GHz CPU and 128 MB RAM, so it’s noticeably better for multi-user use and heavier tasks. Both are 2-bay units with no expansion, and neither supports 10GbE or M.2.