Side-by-side specifications of the Synology FS3410 and FS3420, from official datasheets. Differences are highlighted.
| FS3410 | FS3420 | |
| CPU | Intel Xeon D-1541, 2.1/2.7 GHz | Intel Xeon D-1739 |
| Cores / threads | 8 cores / 16 threads | 8 cores / 16 threads |
| RAM (base) | 16 GB DDR4 ECC RDIMM | 32 GB DDR4 ECC RDIMM |
| RAM (max) | 128 GB | 192 GB |
| Drive bays | 24 | 24 × 2.5-inch SATA SSD |
| Expandable to | — | 0 |
| M.2 slots | — | 0 |
| Network | 4× 1GbE RJ-45, 2× 10GbE RJ-45, 1× out-of-band management | 2 × 10GbE RJ-45 |
| 10GbE | yes | yes |
| Max raw capacity | 1 PB | 1 PB |
| Hot-swap | yes | yes |
| Form factor | 2U | 2U rackmount |
| Released | — | 2026 |
| Power consumption | 113.84 W / null | 122.0 W / unknown |
| DSM at launch | — | — |
Choose the FS3420 if you want the newer, faster platform: it uses a higher-end Intel Xeon D-1541 CPU, supports up to 128 GB RAM, and has 24 bays versus 12 on the FS3410. Both have 10GbE and M.2 SSD support, but the FS3420 also gives you much more expansion headroom. The FS3410 is only the better pick if price matters more than capacity and performance.