Synology today announced the US availability of its third 2025 NAS server, the DiskStation DS1525+.
As the name suggests, it’s the five-bay model upgrade to the DS1522+, which was released a few years ago. The new server appears to have all that the previous model offers and then some significant improvements.
Synology DS1525+: Dual 2.5GbE port with 10GbE upgrade option
The first thing to note about the DS1525+ is that, like all 2025 Plus models, it comes with Synology’s new storage requirement: it won’t work with third-party drives that are not on the approved list. To put it bluntly, you’ll have to get hard drives and SSDs from Synology.
That aside, the new server’s name means it features five native drive bays to accommodate up to five internal drives, as well as the option to host two expansion units, allowing for a total of 10 additional drives. In all, it can handle a few hundred terabytes of storage space when fully loaded.
Similar to the previously announced DS925+, the DS1525+ also utilizes a USB-C port for storage expansion and requires the new DX525. Its USB-C expansion ports feature USB 3.2 Gen 1 (a.k.a. USB 3.0), which caps at 5Gbps. It’s a bit disappointing that Synology doesn’t use Thunderbolt or a faster USB grade for them.
In terms of network connectivity, the DS1525+ is a major upgrade to the previous model. It forgoes Gigabit entirely and instead comes with two 2.5GbE ports. Additionally, like the case of the DS1522+, it also has a Network Upgrade slot that can house a Synology E10G22-T1-Mini module that quickly adds 10Gbps capability.
Physically, the new server retains the design that’s been consistent in all previous DS15xx+ servers. The table below shows how this lineup has evolved over the years since the first DS1511+ was released in 2011.
Synology DS15xx+ servers: Hardware specifications
| DS1525+ | DS1522+ | DS1520+ | DS1517+ | DS1515+ | DS1513+ | DS1511+ | |
|---|---|---|---|---|---|---|---|
| Model Year | 2025 | 2022 | 2020 | 2017 | 2015 | 2013 | 2011 |
| Gigabit Port | none | 4 | |||||
| Multi-Gig Port | 2x 2.5GbE | None | |||||
| Dimensions | 16.6 x 23 x 22.3 cm | ||||||
| Weight | 2.67 kg | ||||||
| USB Port | 2x USB 3.0 | 2x USB 3.0 | 2x USB 3.0 | 4x USB 3.0 | 4x USB 3.0 | 2x USB 3.0, 4x USB 2.0 |
4x USB 2.0 |
| Expansion Port | 2x USB-C (USB 3.0) | 2x eSATA | |||||
| CPU | 2.2 GHz AMD Ryzen V1500B Quad-core (8 Threads) |
2.6 GHz AMD Ryzen R1600 Dual-Core (4 Threads) |
2.0GHz Intel Celeron J4125 Quad-Core |
2.4 GHz Intel Atom C2538 Quad-Core | 2.4 GHz Intel Atom C2538 Quad-Core | 2.13 GHz Intel Atom Dual Core |
1.8GHz Intel Daul-Core |
| RAM | 8GB (Expandable to 32GB) |
8GB (Expandable to 20GB) |
2GB (Expandable to 16GB) |
2GB (Expandable to 4GB) | 1GB (Expandable to 3GB) |
||
| Built-in NVMe M.2 slot | 2 (caching or storage) |
None | |||||
| PCIe slot (upgrade) |
None | 1x 8-lane PCIe slot | None | ||||
| Upgrade Options |
Synology E10G22-T1-Mini (1x 10Gbps BASE-T) |
None | Synology E10G21-F2 (2x SFP+ port) Synology E10G18-T1 (1x 10Gbps BASE-T) Synology E10M20-T1 (1x 10Gbps BASE-T, 2x NVMe M.2 slot) |
None | |||
DS1525+ vs DS1522+: A quick assessment
As shown above, the DS1525+ has a minor upgrade in processing power compared to its predecessor. It features an older but more powerful CPU. Considering the new network ports, it will be much faster out of the box.
However, with the 10GbE upgrade, the older DS1522+ will achieve similar throughput speeds. That, plus the fact that it doesn’t require Synology-branded storage, means for now, it’s a better deal for those needing a five-bay server.
DS1525+: A familiar five-bay Synology experience
Besides the hardware specifications above and the new drive requirements, running DSM 7, the new DS1525+ is slated to offer a familiar NAS experience to existing Synology servers. You can expect advanced features and functionalities via different software packages or apps.
In my experience, five is a significant number among Plus servers, as it provides users with all possible RAID configurations and the option to have sufficient storage space before resorting to an expansion unit.
Availability and pricing
According to Synology, the DiskStation DS1525+ is now available for purchase with a suggested retail price similar to that of the DS1522+, which is $750 (diskless). However, considering the new storage requirement, it will likely have a much higher total cost of ownership.
