Which Synology NAS should you buy?
DS925+ and DS923+ share four bays, ECC memory and two M.2 slots, but the upgrade paths differ. DS925+ brings a four-core V1500B, dual 2.5GbE and DX525 support; DS923+ uses a two-core R1600, dual 1GbE, optional 10GbE and DX517.
The short answer
DS925+ or DS923+: which should you choose?
Buy DS925+ for stronger general CPU headroom and built-in multi-gig networking. Consider DS923+ when its price is meaningfully lower, you already own DX517, or the official E10G22-T1-Mini 10GbE upgrade matters more than dual 2.5GbE.
What matters before buying: Include network adapters, switch ports, expansion units, memory and drive-policy consequences. Neither model has the Intel Quick Sync path, so a Plex transcoding requirement does not automatically favor the newer chassis.
Compare DS925+ and DS923+ offers
DS925+ vs DS923+ prices
Compare the cost of both four-bay NAS systems, including whether drives are included, before choosing between them.
At a glance
Which option makes sense for your setup?
Interactive decision tool
DS925+ vs DS923+ Decision Tool
Enter how you will use the NAS. The recommendation helps narrow the choices; always confirm exact hardware specifications, current compatibility and the final purchase price.
Buying guide
Everything to check before you buy
Compare the actual hardware, software support and total configured cost. The recommendations below apply to the models named in this guide.
DS925+ or DS923+: which should you buy?
Choose DS925+ when you want a new four-bay Synology with a faster four-core Ryzen V1500B and built-in dual 2.5GbE. The DS923+ can still make sense if the sale price is substantially lower, you already own a compatible DX517 expansion unit, or you need its supported optional 10GbE network adapter path.
These are both serious NAS systems with ECC RAM and two M.2 slots. Neither has the Intel integrated-graphics advantage that some Plex shoppers expect. For backup and file service, buy the one whose whole deployment better matches your existing network and storage plans.
CPU and applications: four cores versus two
DS925+ uses the four-core/eight-thread Ryzen V1500B; DS923+ uses the dual-core/four-thread Ryzen R1600. That extra concurrency can benefit busy application mixes, indexing and simultaneous clients, although disk and network throughput may dominate basic file transfer performance.
Neither CPU turns the NAS into a powerful AI inference workstation. For a single SMB file share or nightly backup, do not overpay just for theoretical core count; examine app requirements and concurrent users.
Built-in 2.5GbE versus optional 10GbE
DS925+ has dual built-in 2.5GbE, useful if your switch and computers already support multi-gig Ethernet. DS923+ starts with gigabit ports but supports the E10G22-T1-Mini 10GbE upgrade. A single fast workstation can favor 10GbE, whereas modest multi-client use may fit DS925+ without an expansion card.
Include the price of the NIC, compatible switch ports and cabling when comparing systems. Link aggregation does not automatically give one file transfer the sum of all port speeds.
Expansion compatibility may decide the purchase
DS925+ uses DX525 expansion hardware, while DS923+ belongs to the DX517 generation. If you already own a DX517 and rely on it, moving to the newer model can involve additional costs beyond the enclosure price.
For first-time buyers, a larger five- or eight-bay chassis may provide better value than buying four bays today and a second enclosure later. Keep backup copies outside the same failure domain.
Memory, NVMe and DSM compatibility
Both models support ECC memory upgrades within Synology's module guidance and provide M.2 slots, but they do not have identical expansion paths or necessarily identical M.2 support by DSM release. The storage-pool rules for NVMe differ from standard SATA hard-drive use.
The broadened DSM 7.3 third-party HDD policy for 2025 DiskStation Plus models does not automatically apply to older DS923+. Check the drive compatibility tool against the exact enclosure and DSM version before reusing disks from another NAS.
Is either one the better Plex NAS?
Both use AMD Ryzen processors without Intel Quick Sync. They handle direct-play media and file serving, but shoppers who routinely need hardware video transcoding should consider Intel-equipped models or a separate media server.
A large library does not itself demand transcoding: the client codec mix, remote bandwidth and subtitles determine whether live conversion is needed. Avoid marketing that equates four bays with better Plex encoding.
Common questions
Common questions answered
Is DS925+ faster than DS923+?
DS925+ has twice the listed CPU cores and built-in 2.5GbE, so it offers more general headroom. Exact application performance still depends on memory, drives and workload.
Which model supports 10GbE?
DS923+ supports the E10G22-T1-Mini 10GbE adapter. DS925+ instead provides dual 2.5GbE built in.
Can DX517 be used with DS925+?
DS925+ uses the DX525 expansion unit. Verify model-specific expansion support rather than assuming the connectors are interchangeable.
Do both models support ECC RAM?
Yes. Both are listed with DDR4 ECC SODIMM memory and a 32GB maximum using supported modules/configurations.
Which is better for Plex transcoding?
Neither has an Intel integrated GPU. Direct play can work well; frequent hardware transcoding may be better handled by external compute.
Can both create M.2 storage pools?
Both appear on Synology’s supported-model list, but compatible Synology M.2 SSDs are required for the supported storage-pool path.
Does DSM 7.3 third-party drive flexibility apply to DS923+?
Synology states that the new 2025 compatibility policies are not retroactive to models launched before 2025.
Should a DS923+ owner upgrade?
Only when dual 2.5GbE, extra CPU cores, current support or DX525 strategy solves a real need. A stable DS923+ can remain useful.
Which has the better expansion path?
Both can reach nine bays, but with different expansion units. The better path depends partly on which enclosure you already own.
Which is the better value?
DS925+ is the safer new-buy default. A discounted DS923+ can be better when optional 10GbE or legacy accessories matter.
Synology specifications and compatibility
Specifications and compatibility guidance come from the Synology product and support documents linked below. Check current Amazon prices and the seller's description before ordering. A price marked as last checked on an earlier date may have changed.
- Synology current Plus-series comparison
- Synology DS925+ and DX525 announcement
- Synology DS923+ announcement
- Synology drive compatibility policies for 2025+ systems
- Synology models supporting M.2 storage pools
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