Side-by-side specifications of the Synology DS423+ and DS723+, from official datasheets. Differences are highlighted.
| DS423+ | DS723+ | |
| CPU | Intel Celeron J4125 | AMD Ryzen R1600 |
| Cores / threads | 4 | 2/4 |
| RAM (base) | 2 GB | 2 GB |
| RAM (max) | 6 GB | 32 GB |
| Drive bays | 4 | 2 |
| Expandable to | 0 | 5 |
| M.2 slots | 2 | 2 |
| Network | 2 x 1GbE RJ-45 | 2x 1GbE |
| 10GbE | no | optional |
| Max raw capacity | 108 TB | 7 drives |
| Hot-swap | yes | yes |
| Form factor | Desktop | desktop |
| Released | 2023 | 2023 |
Choose the DS423+ if you want 4 bays out of the box, because it gives you more direct storage now and is the better fit for a typical home NAS. Choose the DS723+ if you care more about upgrade path and speed potential: it has a newer Ryzen-class CPU, a higher RAM ceiling, dual M.2 slots, 10GbE expansion support, but only 2 bays until you add the expansion unit.