How much RAM does your NAS need? Synology, QNAP and UGREEN upgrades

Your NAS was perfectly happy storing files. Then you added photo indexing, a few containers and a virtual machine—and now opening its dashboard feels like asking it to climb stairs. More RAM can give those jobs room to breathe. First, find out whether memory is the thing holding them up.

Keep the factory RAM for straightforward file sharing when memory pressure is low. Upgrade for apps and VMs when the workload needs it, then shop by the exact NAS model and module part number. For the models below, that means a supported 4 GB expansion for a small Synology Plus, matched QNAP modules for a socketed TS-264, or a 16 GB replacement for UGREEN’s DXP2800.

This research-based guide uses NAS-maker specifications, installation manuals and Kingston’s model-specific memory finder.

How much RAM do you actually need?

Start with the jobs you want your NAS to do. These are planning starting points, not memory requirements for every app.

Your workload	Starting point	What to do next
File shares, scheduled backups and a few users	Keep the installed RAM first; 2–4 GB can suit light duties	Watch the normal workload before buying
Several always-running apps or containers	Around 8 GB	Look for memory pressure when those apps overlap
Busier containers or a small VM workload	Around 16 GB	Add the guests’ assigned RAM and leave room for the NAS
Several VMs or demanding applications	Work out the allocation first	Choose a platform with the supported capacity you need

A simple example: allow 2 GB for the NAS and services, 4 GB for one VM, 4 GB for another and 2 GB of headroom. That adds up to 12 GB, making a supported 16 GB configuration a sensible shopping target. Those are chosen example allocations; use your applications’ requirements for your own sum.

A DS225+ cannot become a supported 16 GB VM host through wishful shopping. Its official ceiling is 6 GB. If your workload needs more than that, change the workload or the platform. Our DXP2800 vs DS225+ comparison shows where those two boxes—and the larger DXP4800 Plus—fit.

Before buying, watch cache and swap

In DSM, open Resource Monitor → Performance and inspect memory and swap while your usual jobs run. A full-looking memory chart alone is a poor shopping signal: DSM uses RAM to cache frequently accessed data and releases that cache when applications need space.

Look for memory pressure that coincides with the slowdown. Synology’s Resource Monitor documentation explains cache and swap, including how high swap use affects performance. Watch CPU, disk and network activity too. A busy processor or saturated connection calls for a different fix.

Try the same workload with a nonessential app stopped. If the system becomes comfortable again, you have a useful choice: keep that app elsewhere or give the NAS more memory. You do not need to fill every slot just because the lid comes off.

The model limits that decide the purchase

NAS	Factory memory	Upgrade layout	Official maximum	Module route
Synology DS225+	2 GB DDR4 non-ECC	One expansion SO-DIMM slot alongside the base memory	6 GB: 2 + 4 GB	Current listed D4NS01-4G
Synology DS224+	2 GB DDR4 non-ECC	One expansion SO-DIMM slot alongside the base memory	6 GB: 2 + 4 GB	D4NESO-2666-4G is listed in its official module sheet; current D4NS01-4G list also includes DS224+
QNAP TS-264-8G, socketed version since January 2024	8 GB DDR4 SO-DIMM	Two DDR4 SO-DIMM slots	16 GB: 2 × 8 GB	Matched QNAP modules approved for the model
Original fixed-memory TS-264	8 GB	Non-expandable in its original manual	8 GB	Keep the fixed memory
UGREEN DXP2800	8 GB DDR5	One socket; replace the original module	16 GB	Kingston lists KVR56S46BS8-16 for this model

The DS225+ specification, DS224+ specification, current TS-264 specification and DXP2800 page supply the model ceilings. Kingston’s DXP2800 finder identifies its removable module and single socket.

Treat fixed onboard memory as fixed. On the small Synology models, the upgrade is the extra module, not replacement of the base memory; on DXP2800, it is a replacement. QNAP needs particular attention because the same TS-264 name spans different memory layouts.

Synology: follow the whole part number

For DS224+, Synology’s D4NESO-2666-4G specification sheet explicitly lists the model. It is a genuine 4 GB DDR4 non-ECC unbuffered SO-DIMM; adding it to the base 2 GB gives 6 GB total. That sheet also lists DS220+, DS423+ and several older models.

For DS225+, choose D4NS01-4G, the module on its current specification and Synology’s memory-module page. Use that maker page for the current approved part. Similar-looking names are worth reading all the way to the end.

ECC is a separate branch of the family. D4ES02-8G is an 8 GB DDR4 ECC unbuffered SO-DIMM listed for models including DS923+, DS723+ and DS1522+. It is not the non-ECC expansion for DS225+. The same Synology module list separates these families.

Choose the required ECC type as well as the capacity. A module fitting the socket does not turn a non-ECC platform into an ECC system; our ECC RAM guide explains the CPU-and-board side. Synology also limits complete warranty/support coverage for third-party memory upgrades, so the picks here follow its own module documentation.

QNAP: identify the revision, then match the modules

Current TS-264 specifications describe 8 GB SO-DIMM memory since January 2024, two slots and a maximum of 16 GB as two 8 GB modules. The accessories list names RAM-8GDR4D0-SO-3200 and RAM-8GDR4K0-SO-3200. Follow the exact version and matching-module guidance on the QNAP accessories page.

The original TS-x62/x64 manual describes TS-264 with non-expandable 8 GB memory. Its memory-replacement chapter covers other socketed members of the family. That explains why a blanket “all TS-264 units take two sticks” instruction sends owners in the wrong direction.

Identify your unit’s actual layout before ordering. If it has fixed memory, spend the effort on moving an app or choosing another host. If it has the supported slots, use QNAP modules with identical specifications; the maker explicitly calls for matched modules. A generic laptop kit is not the maker-supported route here.

UGREEN: one 16 GB stick, not two

DXP2800 ships with 8 GB DDR5 and has an official 16 GB maximum. Kingston’s model finder lists KVR56S46BS8-16, a 16 GB DDR5-5600 non-ECC SO-DIMM, for that exact NAS. It also explains that faster memory clocks down to the speed supported by the installed processor.

This is Kingston’s compatibility recommendation, rather than a claim of UGREEN QVL approval. Keep UGREEN’s 16 GB ceiling: replace the original 8 GB with the 16 GB module, giving 16 GB total and an 8 GB increase. There is no second memory socket to fill.

The Kingston datasheet identifies the part’s 262-pin SO-DIMM format, 1.1 V operation and CL46 DDR5-5600 specification. Buy that exact part rather than transferring the recommendation to a desktop DIMM, another capacity or a similarly named kit.

Install it, then check DSM or QTS

Make the software check part of the upgrade. Finish with the right total in the dashboard.

1. Record the starting point. Note the installed capacity, module labels and exact NAS model/revision. Have a current backup before maintenance; RAM does not replace a backup destination.
2. Shut down cleanly and unplug. Stop the NAS through its interface, disconnect power and cables, and follow the maker’s anti-static handling instructions. Hold modules by their edges.
3. Use the access route for your model. DS225+’s installation guide places its expansion slot behind the drive trays on the inner-right side. Keep tray order intact. Other cases have their own access panels and procedures.
4. Seat the module. Align the notch, insert it fully and engage the retaining clips as the manual shows. Fit an expansion module or replace the original according to the layout above.
5. Reassemble and boot. Restore the trays, panels and cables, then let the NAS start normally.
6. Read the total. In DSM, open Control Panel → Info Center → Total Physical Memory. In QTS, use Control Panel → System → System Status → Hardware Information → Total memory, as shown in the QNAP manual.
7. Run your usual jobs again. Check that applications start, shares open and the next backup completes. Compare memory pressure during the workload that prompted the upgrade.

If the NAS will not start or reports the old capacity, shut it down and disconnect power before reseating the module. Restore the original configuration if necessary, then resolve the part or seating issue before returning it to regular duty.

The useful upgrade is the one your workload needs

For a supported DS224+ expansion, choose the genuine D4NESO-2666-4G; for DS225+, follow the current D4NS01-4G maker listing. For socketed TS-264 units, use matched approved QNAP modules. For DXP2800, Kingston’s listed 16 GB module is the straightforward replacement path.

Keep the factory memory when it already handles your jobs. If you need more capacity than the platform officially supports, our NAS comparison helps you choose the next box. Then keep an independent recovery copy with the RAID, snapshots and backups guide. More breathing room is great; knowing why you bought it is better.