Best RAM Upgrade for Synology DS423+ (2026 Guide)

Best RAM upgrades for the DS423+

The DS423+ has one free SODIMM slot alongside its onboard 2GB, so these are the sensible fits.

Which should you pick

Why 6GB is the practical ceiling here

The DS423+ ships with 2GB of DDR4 soldered or fixed in one bank, plus a single accessible SODIMM slot. Synology officially caps this model at 6GB total, so the only sensible upgrade path is adding one 4GB module to replace or sit alongside the factory stick, depending on your unit's configuration. Trying to push beyond this with an 8GB module is unsupported by DSM and won't be recognised reliably, so there is no benefit in buying a larger kit here.

For most DS423+ owners, this is genuinely enough. The J4125 is a capable but modest quad-core chip, and the workloads this NAS is built for, SMB and AFP file serving, Time Machine backups, Synology Photos for a household, and basic Docker containers such as Pi-hole or a lightweight app, do not lean heavily on RAM. Where you will feel the pinch is if you start running multiple containers simultaneously or lean on Synology's search indexing across a large photo library, in which case 6GB smooths things out compared with the stock 2GB.

Be honest about transcoding before you buy anything