Synology DS1825+: Specs, Drive Compatibility and Total Build Cost
The DS1825+ is Synology's 8-bay Plus-series DiskStation, and the top of the desktop range this cluster tracks. Below is what Synology's own spec sheet states, what it costs filled with drives at today's prices, and its drive-compatibility position.
Hardware specifications, per Synology's own spec sheet
| Bays | 8 |
|---|---|
| Drive form factors | 8 x 3.5-inch SATA HDD or 2.5-inch SATA SSD |
| M.2 slots | 2 x M.2 2280 NVMe |
| M.2 purpose | SSD cache OR an independent M.2 storage pool |
| Max single-drive capacity | no Synology source found |
| RAM | DDR4 ECC SODIMM, 8GB installed (1 slot used of 2) |
| Network | 2 x 2.5GbE RJ-45 built in; PCIe Gen3 x8 slot documented to support Synology's own 25GbE (E25G30-F2) or 10GbE (E10G30-F2/T2/T1) cards, sold separately |
| Expansion unit | DX525 (up to 2 units) - 18 total bays |
| PSU | 250W |
| Published acoustic figure | 23.8 dB(A), Synology's own stated test method (idle, fully populated, 1m) |
Source: Synology DS1825+ Product Specification, read 2026-09-14 — PDF.
The honest total: chassis + drives, three ways
$1265.16 buys the empty chassis. Eight bays filled is the real purchase, and at this bay count the gap between the three tiers below is the widest in this Synology line.
Best value fill - DS1825+ + 8 drives
Usable capacity by RAID level: RAID 1 32TB ($335.00/usable TB) · RAID 5 224TB ($47.86/usable TB) · RAID 6 192TB ($55.83/usable TB) · RAID 10 128TB ($83.75/usable TB) 9 items across 2 listings. In-stock listings only. Anything out of stock when this page loaded is named below rather than silently dropped.
| Item | Qty | Each | Line | |
|---|---|---|---|---|
| DriveSeagate SkyHawk AI 32TB ST32000VE000 (32TB) | x8 | $1339.99 | $10719.92 | Buy on Amazon |
| ChassisSynology DiskStation DS1825+ 8-Bay | x1 | $1265.16 | $1265.16 | Buy on Amazon |
| Basket total | $11985.08 | |||
These are our current tracked prices. Amazon sets the seller and the final price at checkout - verify before you buy. Opening any item starts an Amazon session, and anything you add there is part of the same order - you do not need to come back here between items.
Enterprise fill - DS1825+ + 8 drives
Usable capacity by RAID level: RAID 1 18TB ($335.55/usable TB) · RAID 5 126TB ($47.94/usable TB) · RAID 6 108TB ($55.93/usable TB) · RAID 10 72TB ($83.89/usable TB) 9 items across 2 listings. In-stock listings only. Anything out of stock when this page loaded is named below rather than silently dropped.
| Item | Qty | Each | Line | |
|---|---|---|---|---|
| DriveWD Red Pro 18TB WD181KFGX (18TB) | x8 | $754.99 | $6039.92 | Buy on Amazon |
| ChassisSynology DiskStation DS1825+ 8-Bay | x1 | $1265.16 | $1265.16 | Buy on Amazon |
| Basket total | $7305.08 | |||
These are our current tracked prices. Amazon sets the seller and the final price at checkout - verify before you buy. Opening any item starts an Amazon session, and anything you add there is part of the same order - you do not need to come back here between items.
Refurbished fill - DS1825+ + 8 drives
Usable capacity by RAID level: RAID 1 14TB ($199.43/usable TB) · RAID 5 98TB ($28.49/usable TB) · RAID 6 84TB ($33.24/usable TB) · RAID 10 56TB ($49.86/usable TB) 9 items across 2 listings. In-stock listings only. Anything out of stock when this page loaded is named below rather than silently dropped.
| Item | Qty | Each | Line | |
|---|---|---|---|---|
| DriveToshiba MG07ACA14TE 14TB SATA Enterprise (14TB) | x8 | $349.00 | $2792.00 | Buy on Amazon |
| ChassisSynology DiskStation DS1825+ 8-Bay | x1 | $1265.16 | $1265.16 | Buy on Amazon |
| Basket total | $4057.16 | |||
These are our current tracked prices. Amazon sets the seller and the final price at checkout - verify before you buy. Opening any item starts an Amazon session, and anything you add there is part of the same order - you do not need to come back here between items.
The smallest cheque that fills all 8 bays, separately from the value tiers above: 8 x Seagate SkyHawk 3TB ST3000VX009 at $165.00 each = $1320.00.
Drive compatibility, measured
Eight bays makes the DS1825+ the machine where drive choice costs the most in absolute terms. It carries exactly the list the two-bay DS225+ does, which is the clearest evidence on this page that Synology's list tracks its own product range rather than any property of the chassis.
133 fit-verified third-party SATA HDDs are in our catalogue right now for this bay class, none on Synology's own list. At eight bays a per-terabyte brand preference compounds the most of any machine in this line.
Measured: at 16TB on SATA, Synology's own drive runs $48.91/TB against $44.25/TB for the cheapest qualifying third-party drive - a +10.5% premium, matched interface to interface, paid eight times over on a full build.
Full DS1825+ compatible-drives page and Synology's drive policy, per series, dated.
What DSM 7.3 lets a drive that is not on Synology's list do in the DS1825+
Synology launched the DS1825+ on 2025-07-08, so its 2025 drive policy applies, and the DS1825+ is in the DS Plus and desktop models of FS series table. For a drive that is not on Synology's compatibility list:
- HDD: New pool and migration
- 2.5" SATA SSD: New pool, cache and migration
- M.2 NVMe SSD: Migration only
So on the DS1825+ a third-party hard drive can build a new storage pool; Storage Manager shows it as Unverified. A drive on Synology's incompatibility list is not supported for a new installation or storage pool, for cache, or for migration - on every series.
Source: Synology, DSM 7.3, last updated 27 May 2026. The full DS1825+ drive-policy page has every cell, the incompatibility list and drives in stock that fit.
Expansion limits and the M.2 reality
DX525 (up to 2 units) - 18 total bays. The DS1825+ is also the one model in this Synology line with a documented path past 10GbE: its PCIe Gen3 x8 slot supports Synology's own 25GbE card (E25G30-F2) as well as 10GbE cards, sold separately - neither the DS925+ nor the DS1525+ in the same generation document a 25GbE option.
The M.2 slots follow the rest of the Plus generation: both SSD read/write cache and an independent M.2 storage pool are supported, not cache-only, with Synology-verified SSDs required specifically for the storage-pool path per Synology's own footnote.
Eight bays is also where the RAID 5 versus RAID 6 gap is largest in absolute terms among the models this cluster tracks. RAID 5 across eight drives loses one drive of capacity to parity; RAID 6 loses two, and gains tolerance for a second drive failing during what is, at today's large drive sizes, a rebuild window measured in the better part of a day. The usable-capacity figures in the baskets above show both levels side by side rather than defaulting to one - at this bay count the choice is a real trade-off, not a formality.
What else it needs
Power protection: eight drives is enough that a UPS stops being optional - see UPS units for a NAS, priced live with output waveform stated. If a 10GbE or 25GbE card goes in the PCIe slot, the switch and cabling on the other end need to match it - see 25/40/100GbE hub and 10GbE for a NAS for live card, cable and switch prices.
Frequently asked questions
Frequently asked questions
How many drives does the DS1825+ take?
8, all 3.5-inch SATA HDD or 2.5-inch SATA SSD bays per Synology's own spec sheet, plus two M.2 2280 NVMe slots for cache or an independent storage pool.
What's the maximum capacity of the DS1825+?
Synology's own spec sheet publishes no maximum single-drive capacity for this model. With the DX525 expansion unit (up to two units), Synology documents 18 total bays.
Can I use third-party drives in the DS1825+?
Yes. Synology's own list for the DS1825+ names 22 hard drives, all Synology's own HAT series - but the DS1825+ is a Plus-tier machine, and an unlisted hard drive still creates a storage pool on it, labelled Unverified in DSM rather than refused.
Does the DS1825+ support 25GbE?
Documented, not standard. Synology lists a PCIe Gen3 x8 slot for this model that supports its own 25GbE card (E25G30-F2) or 10GbE cards (E10G30-F2/T2/T1), sold separately - the only model in Synology's current desktop DiskStation range we found with a documented 25GbE option at all.
What does a complete DS1825+ build cost?
$1265.16 for the chassis alone; $10719.92 filled with 8 best-value drives, or as little as $1320.00 for the smallest qualifying set.
Why does the DS1825+ have a bigger power supply than the smaller models?
Synology documents a 250W supply for this model, against 100W on the 4-bay DS925+ and 120W on the 5-bay DS1525+ - eight spinning drives plus PCIe card headroom draws more than four or five, and Synology's own spec sheet sizes the PSU accordingly.
Sources checked: Synology DS1825+ product page, Synology DS1825+ Product Specification (PDF), Synology compatibility search.