Main trade-off
QNAP TS-264-8G-US
Two SATA bays constrain hard-drive growth.
Head-to-head
QNAP TS-264 vs Synology DS425+: Synology adds HDD bays, QNAP leaves a network-card route
The short answer
Choose TS-264-8G if two hard drives are enough and you want more installed RAM or a PCIe network-upgrade route. Choose DS425+ for a larger internal hard-drive array and DSM backups. Both have two NVMe slots, so the main decision is storage growth versus hardware flexibility around a smaller drive pair.
Before you choose
The reasoning and the trade-offs
Four bays can provide 24 TB more in the same drive-size example
With equal compatible 12 TB drives, QNAP's two-drive mirror offers 12 TB before overhead. A four-drive RAID 5 array in DS425+ offers 36 TB. The extra 24 TB comes from two more purchased drives and a different RAID layout, not from the enclosure alone.
What this is based on
QNAP RAID 1: 12 TB. Synology RAID 5: (4 - 1) × 12 = 36 TB. 36 - 12 = 24 TB additional nominal usable capacity.
Main trade-off
Synology DiskStation DS425+
Only 2 GB RAM is supplied, with a 6 GB official maximum.
QNAP TS-264-8G-US
- Choose it for
- Keep two hard drives with 8 GB RAM already installed
- Retain a compatible PCIe networking upgrade path
- Main trade-off
- Two SATA bays constrain hard-drive growth.
Synology DiskStation DS425+
- Choose it for
- Grow to three or four internal hard drives
- Use RAID 6 with four drives and the DSM workflow
- Main trade-off
- Only 2 GB RAM is supplied, with a 6 GB official maximum.
About this comparison
QNAP TS-264 vs Synology DS425+ for storage growth and home apps. Compare protected hard-drive capacity, RAM and networking before buying a diskless NAS.
Choose TS-264-8G if two hard drives are enough and you want more installed RAM or a PCIe network-upgrade route. Choose DS425+ for a larger internal hard-drive array and DSM backups. Both have two NVMe slots, so the main decision is storage growth versus hardware flexibility around a smaller drive pair.
Winner by situation
Start with what you need it to do
Two mirrored hard drives cover my long-term storage need
Both can use that starting layout. QNAP adds more supplied memory.
- QNAP TS-264-8G-US
- Good
- Synology DiskStation DS425+
- Good
I want four hard drives in one internal array
DS425+ provides four SATA bays.
- QNAP TS-264-8G-US
- Not suitable
- Synology DiskStation DS425+
- Better fit
My applications require 8 GB of RAM
The QNAP 8G model includes that memory. Synology officially supports up to 6 GB.
- QNAP TS-264-8G-US
- Good
- Synology DiskStation DS425+
- Not suitable
I need two NVMe positions alongside hard drives
Both provide two slots, with platform-specific drive and storage-mode requirements.
- QNAP TS-264-8G-US
- Good
- Synology DiskStation DS425+
- Good
What matters in practice
The differences that matter
Four bays can provide 24 TB more in the same drive-size example
With equal compatible 12 TB drives, QNAP's two-drive mirror offers 12 TB before overhead. A four-drive RAID 5 array in DS425+ offers 36 TB. The extra 24 TB comes from two more purchased drives and a different RAID layout, not from the enclosure alone.
How we reached this conclusion
QNAP RAID 1: 12 TB. Synology RAID 5: (4 - 1) × 12 = 36 TB. 36 - 12 = 24 TB additional nominal usable capacity.
The smaller chassis starts above Synology's official RAM ceiling
The selected TS-264-8G arrives with 8 GB. DS425+ officially supports up to 6 GB, even after expansion. If your chosen applications genuinely require 8 GB, Synology's additional hard-drive bays do not solve that memory requirement.
How we reached this conclusion
QNAP includes 8 GB. Synology's maximum is 6 GB. 8 - 6 = 2 GB above the official Synology ceiling.
Two-drive fault tolerance requires the right hard-drive layout
Four equal 12 TB drives in Synology RAID 6 provide 24 TB before overhead and tolerate two drive failures. A two-drive mirror in QNAP tolerates one. Two NVMe slots do not turn QNAP into a four-hard-drive chassis.
How we reached this conclusion
RAID 6: (4 - 2) × 12 = 24 TB with two-drive fault tolerance. Two-drive RAID 1 retains one drive's capacity and tolerates one drive failure.
Choice A
QNAP, TS-264-8G-US
QNAP TS-264-8G-US
A two-bay NAS with two built-in NVMe slots, dual 2.5GbE and a PCIe slot for supported SSD or network expansion. The selected current 8G configuration supplies 8 GB RAM.
- Best matched use
- Keep two hard drives with 8 GB RAM already installed
Checked facts
- SATA drive bays: 2
- NVMe slots: 2
- Installed memory: 8 GB
- Official maximum memory: 16 GB on the current SODIMM revision
Choice B
Synology, DS425+
Synology DiskStation DS425+
The chassis has 4-bay storage. Its fastest documented network path is 2.5 Gbps.
- Best matched use
- Grow to three or four internal hard drives
Checked facts
- SATA drive bays: 4
- NVMe slots: 2
- Installed memory: 2 GB
- Official maximum memory: 6 GB
Meaningful differences
What changes the fit
| What changes | QNAP TS-264-8G-US | Synology DiskStation DS425+ | Why it matters |
|---|---|---|---|
| SATA drive bays | 2 | 4 | Synology supports a larger internal hard-drive array. |
| NVMe slots | 2 | 2 | Neither has a slot-count advantage for a two-NVMe plan. |
| Installed memory | 8 GB | 2 GB | QNAP includes more RAM despite the smaller hard-drive chassis. |
| Official maximum memory | 16 GB on the current SODIMM revision | 6 GB | Confirm QNAP revision and supported modules before upgrading. |
| Built-in Ethernet | Two 2.5GbE | One 2.5GbE and one 1GbE | Both can use a single 2.5GbE client path. |
| PCIe network expansion | One slot with compatible card options | No internal PCIe card slot | QNAP can add supported faster networking, at additional cost. |
What you give up
Every choice has a cost
If you choose QNAP TS-264-8G-US
- Optional network expansion costs extra and uses its single PCIe slot.
If you choose Synology DiskStation DS425+
- No internal PCIe card upgrade path.
Recommendation switch
The decision flips if...
My next step is three or four internal hard drives
Choose Synology DiskStation DS425+. DS425+ provides the additional SATA positions.
Two hard drives are enough and 8 GB RAM is required now
Choose QNAP TS-264-8G-US. The selected QNAP 8G model supplies that memory.
I need both four SATA bays and more than 6 GB officially supported RAM
Choose neither. This combination requires another model.
What matters in practice
How to make the call
Put the storage plan and app plan on separate lines
A four-bay NAS is not automatically a more capable application server. DS425+ has more SATA positions, while TS-264-8G has more supplied memory and a PCIe slot. Estimate the protected storage capacity first, then check the CPU and memory requirements of the applications you plan to run.
Allow for the drives in the four-bay budget
The larger RAID examples assume four purchased drives. Buying a four-bay enclosure with only two drives initially does not immediately create four-drive RAID 5 or RAID 6 capacity. Check the supported migration path and keep a verified backup before changing an array later.
Do not confuse NVMe presence with unrestricted SSD support
Both have two M.2 positions. Synology permits M.2 storage pools with its verified SSD requirements, while QNAP also requires checking drive compatibility and the chosen storage mode. The same physical drive size is not enough to establish that an SSD will work as planned on both systems.
What this comparison cannot tell you
- Storage calculations use equal-capacity compatible drives and decimal TB before formatting, system space and metadata. RAID protects against specified drive failures but does not replace a separate backup.
- Network figures are link rates rather than measured file-transfer speeds. Software support, memory revision, drive compatibility and the rest of the network must be checked for the exact purchase.
What the facts say
What the comparison shows
Useful conclusions from the current NAS devices comparison, followed by the checked facts used to reach them.
See the checked facts and calculation notes
| Product | Needs matched | Checked facts | Source records |
|---|---|---|---|
| QNAP TS-264-8G-US |
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| Synology DiskStation DS425+ |
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Ready to choose?
Check the price. Read the owner reviews.
Open either model on Amazon to check the current price, customer reviews and delivery options.
QNAP TS-264-8G-US
Keep two hard drives with 8 GB RAM already installed
See price & reviews on AmazonSynology DiskStation DS425+
Grow to three or four internal hard drives
See price & reviews on AmazonLinks open in a new tab.