Comparison

Compare two-bay Synology models without confusing the names

Synology's Plus models use names that can make two-bay and four-bay choices look closer than they are. The DS225+, DS425+, DS725+ and DS925+ comparison remains useful for the original family distinctions, but the current lineup also includes separately named neo+ memory configurations. It shows that bay count is only one difference: memory, processor, M.2 slots, expansion, Ethernet and storage modes do not all track together.

DS225+ and DS425+: same CPU, different storage footprint

The comparison lists both DS225+ and DS425+ with an Intel Celeron J4125 processor, 2 GB of non-ECC memory and one 2.5GbE plus one 1GbE port. The DS225+ has two 3.5-inch SATA HDD or 2.5-inch SATA SSD bays. The DS425+ has four such SATA bays and two M.2 2280 NVMe SSD slots. The four-bay unit also lists a higher power adapter, different dimensions and weight, and a higher idle-noise figure under the manufacturer's test. If you are deciding between the two, the DS425+'s extra positions and M.2 support are the meaningful hardware changes; the product name does not indicate a faster Ethernet rate.

Those extra bays can create more options for capacity and supported layouts, but they do not automatically double usable space or make backup unnecessary. Check the drive count required by the layout you want and keep the exact compatible drives in view.

DS725+: two SATA bays with a documented expansion route

The DS725+ is also a two-SATA-bay model, but the comparison lists two M.2 slots, 4 GB of ECC memory, an AMD Ryzen R1600 processor and a USB-C expansion port. With the DX525 expansion unit, Synology lists up to seven drive bays. That is a documented expansion path in the comparison, not a reason to assume that any USB enclosure can be attached as an array expansion. Verify the exact unit and supported storage migration plan before depending on future growth.

DS725neo+: same chassis plan, different default memory

Synology's separate DS725+ and DS725neo+ comparison lists the same Ryzen R1600, two SATA bays, one 2.5GbE and one 1GbE port, two M.2 positions and a seven-drive DX525 expansion route. The material initial difference is memory: DS725+ is listed with 4 GB ECC SODIMM; DS725neo+ with 4 GB non-ECC SODIMM. Synology says ECC upgrades are supported, but mixing ECC and non-ECC memory is not officially supported. Confirm the complete model suffix and manufacturer-approved module configuration rather than treating “neo” as a packaging option.

The model support table now lists DS725neo+ among systems that can use compatible Synology M.2 SSDs to create a storage pool. The DS725neo+ datasheet still highlights caching. If M.2 pool creation is essential, verify the current compatibility list and DSM details before selecting an SSD; the slots are not hot-pluggable, and the M.2 devices do not replace the drives needed to install DSM.

DS925+: more internal bays and two 2.5GbE ports

The DS925+ uses an AMD Ryzen V1500B processor, 4 GB of ECC memory, four SATA bays, two M.2 2280 slots and two 2.5GbE ports. The comparison lists it up to nine total bays with the DX525. That makes it a materially different starting point from the compact DS225+ if a second multigigabit port, four internal drives or a supported chassis expansion is essential. Actual throughput still depends on the network path, storage layout and workload.

DS925neo+: four bays with a non-ECC starting configuration

The DS925+ and DS925neo+ comparison shows four SATA bays, a Ryzen V1500B, two 2.5GbE ports, two M.2 positions and a DX525 route to nine drives for both models. The DS925neo+ comes with 4 GB non-ECC SODIMM rather than the DS925+'s 4 GB ECC SODIMM. Synology's launch notice permits ECC upgrades but says not to mix ECC and non-ECC modules. The current model-support list explicitly includes DS925neo+ for M.2 storage pools, with compatible Synology NVMe drives; account for compatibility and powered-off M.2 maintenance.

Smaller choices: DS224+, DS223, DS223j and DS124

The small-model comparison shows why the bay count alone is not enough. DS224+ has two SATA bays, an Intel Celeron J4125, 2 GB of non-ECC memory listed expandable to 6 GB, and two 1GbE ports. Those two gigabit links do not add up to a built-in 2.5GbE client port. DS223 is also two-bay, but uses a Realtek RTD1619B with 2 GB of non-ECC memory, one 1GbE port and three USB ports. DS223j shares the Realtek processor and two-bay plan but lists 1 GB of memory, two USB ports and an optional Type C holder for 2.5-inch drives. Both DS223 and DS223j list two-drive SHR/RAID 1 options; check the exact package and compatibility list before choosing media.

The DS124/DS223/DS223j comparison identifies a different constraint: DS124 has one internal bay and Basic storage only. It cannot provide an in-box two-drive mirror; use an independent backup destination if the data needs a recoverable second copy. The one-bay unit may make sense when a compact single-disk shared-storage endpoint is genuinely enough, but it is not an equivalent to the two-bay models.

For buyers who need one built-in 2.5GbE port, compare the newer DS225+ rather than treating the DS224+'s two 1GbE ports as multigigabit. The product comparison distinguishes the link rates alongside bays, memory and M.2 positions. Read each exact assessment before ordering.

What the table cannot decide for you

A hardware table will not tell you the appropriate drive capacity, array mode, complete backup plan or exact retailer package. Synology's product pages warn buyers to check the compatibility list; use the exact NAS model and drive code. The listed maximum volume size is not a usable-capacity estimate. Performance figures are manufacturer results, not an independent test in your home. Compare supported operating arrangements and purchase checks before choosing a chassis.

The source comparison also treats performance figures and noise values as conditional. For example, the DS225+ noise figure is described for an idle unit with Synology SATA HDDs installed at a specified distance and background-noise level. A different drive, room or workload can change what you hear. Use the published result to understand the test context, not as a silent-operation promise.

Quick decision checkpoints

• Choose DS225+ only if two SATA bays, one 2.5GbE port, 2 GB installed memory and no listed M.2 slot fit your plan.
• Consider DS425+ if four internal SATA positions and two M.2 slots are important, while its 2.5GbE + 1GbE network layout still suits you.
• Compare DS725+ and DS725neo+ by exact memory suffix: ECC is the standard + model's default; non-ECC is neo+'s default. Both list two SATA bays, a 2.5GbE plus 1GbE pair and the DX525 route.
• Compare DS925+ and DS925neo+ the same way if four bays and dual 2.5GbE fit; their default ECC versus non-ECC memory is a configuration decision, not an image or package detail.

These are feature distinctions, not a universal ranking. Read the exact model's manual and support list, then check the seller's package. Similar product names do not make the configurations interchangeable.

ASUSTOR NIMBUSTOR 2: a second network port in a two-bay chassis

The AS5202T shares a two-SATA-bay footprint with the AS3302T v2 and AS1202T, but its official hardware profile lists two 2.5GbE ports and memory expandable from 2 GB to a maximum of 8 GB. The AS3302T v2 has one 2.5GbE port with fixed 2 GB in its reviewed profile; the AS1202T has one 2.5GbE port and fixed 1 GB. AS5202T link aggregation is conditional on compatible equipment, not a single-client speed guarantee. Its owner-created two-drive mirror fills the two bays. Read the AS5202T assessment, compare the AS3302T v2, or compare the AS1202T.

There is an unresolved hardware-identity distinction worth checking before a CPU-driven purchase: exact AS5202T material lists a J4005, while official U.S. comparison documents list J4025 and another ASUSTOR comparison page labels an “upgrade version.” No U.S. retail revision bridge was verified. The four-bay AS3304T v2 changes the native-bay count rather than adding a second Ethernet port; compare exact model suffixes and the whole wired path instead of ranking these by name alone.

The AS5202T meets both a two-bay minimum and a 2.5-Gbps single-port floor: its specification lists two native SATA positions and two individual 2.5GbE ports. Link aggregation is a separate compatible-hardware arrangement, not the basis for this one-port rating. Review the NIMBUSTOR 2 assessment or return to the finder with the same bay and port requirements.