Side-by-side specifications of the Synology DVA3221 and SA3400D, from official datasheets. Differences are highlighted.
| DVA3221 | SA3400D | |
| CPU | Intel Atom C3538 | Intel Xeon D-1541 |
| Cores / threads | 4 | 8/16 |
| RAM (base) | 8 GB | 8 GB |
| RAM (max) | 32 GB | 64 GB |
| Drive bays | 4 | 12 |
| Expandable to | 8 | 36 |
| M.2 slots | 0 | 0 |
| Network | 4 x 1GbE | 2x1GbE+1x10GbE per controller |
| 10GbE | no | yes |
| Max raw capacity | 224 TB | 576 TB |
| Hot-swap | yes | yes |
| Form factor | desktop | 2U rack |
| Released | 2020 | 2025 |
Choose the DVA3221 if you want the lighter, video-focused box: it uses an Atom C3538, tops out at 32 GB RAM, has 4 bays, no 10GbE, and no M.2. Choose the SA3400D if you need much more headroom and storage growth: Xeon D-1541, 128 GB RAM max, 12 bays with expansion support, 10GbE, and M.2 support.