Main trade-off
TerraMaster F4-425
The single network port tops out at 2.5GbE.
Head-to-head
TerraMaster F4-425 vs Synology DiskStation DS425+: Synology adds supported M.2 storage beside four hard drives
The short answer
The F4-425 includes 4GB memory and straightforward SATA storage. Choose the DS425+ when DSM applications and its two M.2 slots are part of the purchase brief.
Before you choose
The reasoning and the trade-offs
Protected capacity with equal 12TB drives
F4-425 gives 36TB and Synology DiskStation DS425+ gives 36TB before formatting in this example. Changing chassis does not increase this protected capacity.
What this is based on
Assume every SATA bay contains a supported 12TB disk. Two-bay RAID 1 uses one disk of usable capacity. For three or more drives, RAID 5 usable TB = (drive count minus 1) × 12. This is an illustrative layout, not included storage or a backup.
Main trade-off
Synology DiskStation DS425+
The 2GB base memory is modest for many apps.
TerraMaster F4-425
- Choose it for
- You want 4GB supplied RAM for a SATA archive
- You want 16GB for supported ram ceiling
- Main trade-off
- The single network port tops out at 2.5GbE.
Synology DiskStation DS425+
- Choose it for
- You want DSM and a supported M.2 storage role
- You want 6GB for supported ram ceiling
- Main trade-off
- The 2GB base memory is modest for many apps.
About this comparison
Compare F4-425 and DS425+ by protected storage, included networking and the exact SSD or application layout you need.
This is a choice between a SATA archive and the DSM storage ecosystem.
Winner by situation
Start with what you need it to do
A protected archive using 12 TB disks in every internal SATA bay
Using RAID 1 for two disks or RAID 5 for three or more disks, F4-425 gives 36TB and Synology DiskStation DS425+ gives 36TB before formatting in this example. Changing chassis does not increase this protected capacity.
- TerraMaster F4-425
- Similar
- Synology DiskStation DS425+
- Similar
A workstation already matching the faster included Ethernet port
Included port rates are 2.5GbE and 2.5GbE. Use the 100GB calculation alongside the actual client speed.
- TerraMaster F4-425
- Similar
- Synology DiskStation DS425+
- Similar
Several local services sharing the supplied RAM
TerraMaster F4-425 supplies 4 GB RAM and supports 16 GB. Synology DiskStation DS425+ supplies 2 GB and supports 6 GB. Compare the stated application memory requirement with the supplied configuration before budgeting for an upgrade. RAM capacity alone does not establish application speed.
- TerraMaster F4-425
- Better fit
- Synology DiskStation DS425+
- Depends
Keep four SATA hard drives while adding a supported M.2 SSD mirror
The DS425+ has two M.2 positions, so a two-SSD mirrored pool can leave all four SATA bays for HDDs when supported Synology SSDs are used. The F4-425 has no M.2 positions and would spend SATA bays on that SSD layout.
- TerraMaster F4-425
- Not suitable
- Synology DiskStation DS425+
- Better fit
What matters in practice
The differences that matter
Protected capacity with equal 12TB drives
F4-425 gives 36TB and Synology DiskStation DS425+ gives 36TB before formatting in this example. Changing chassis does not increase this protected capacity.
How we reached this conclusion
Assume every SATA bay contains a supported 12TB disk. Two-bay RAID 1 uses one disk of usable capacity. For three or more drives, RAID 5 usable TB = (drive count minus 1) × 12. This is an illustrative layout, not included storage or a backup.
100GB transfer at the included port ceiling
The line-rate lower bound is 320 seconds for F4-425 and 320 seconds for Synology DiskStation DS425+. Real copies take longer. A 1GbE client makes the lower bound 800 seconds for both.
How we reached this conclusion
Decimal 100GB × 8 = 800 gigabits. Divide 800 by the fastest included port rate, 2.5Gbps or 2.5Gbps. Ignore protocol overhead only for this lower-bound calculation. Optional adapters and aggregated ports are excluded.
Check whether the SSD plan is cache or primary storage
The DS425+ has two M.2 positions, so a two-SSD mirrored pool can leave all four SATA bays for HDDs when supported Synology SSDs are used. The F4-425 has no M.2 positions and would spend SATA bays on that SSD layout.
How we reached this conclusion
DS425+: 2 M.2 positions minus 2 SSDs = 0 spare M.2, with 4 SATA positions preserved. F4-425: 4 SATA positions minus 2 SSDs = 2 for HDDs. Synology-verified SSDs are required for the documented M.2 pool path.
Choice A
TerraMaster, F4-425
F4-425
Four SATA bays give a growing archive more RAID layout choices than a two-bay mirror. A single 2.5GbE port and 4GB memory keep the specification focused on file storage.
- Best matched use
- A growing family archive with four drives
Checked facts
- 4 SATA drive bays and 0 M.2 slots
- 2.5GbE fastest included network port
- 4GB supplied RAM, expandable to 16GB
- Diskless NAS with Intel N5095 processor
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
- protect family photos and start with four drives
Checked facts
- The chassis has 4-bay storage.
- Its fastest documented network path is 2.5 Gbps.
- Plex media serving is supported.
- Camera recording is supported, but the licensed channel count depends on the selected software and plan.
Meaningful differences
What changes the fit
| What changes | TerraMaster F4-425 | Synology DiskStation DS425+ | Why it matters |
|---|---|---|---|
| Supplied RAM | 4GB | 2GB | This is the installed memory budget before purchasing upgrade modules. |
| Supported RAM ceiling | 16GB | 6GB | This sets the manufacturer-supported upgrade ceiling for concurrent services. |
| M.2 storage slots | 0 | 2 | Plan SSD cache and storage pools separately from the SATA archive. |
| Processor | Intel N5095 | Intel Celeron J4125 | Media engines, application architecture and concurrency depend on this platform. |
| Software and expansion route | TOS | DSM | Choose the applications and supported add-ons required for the job. |
What you give up
Every choice has a cost
If you choose TerraMaster F4-425
- No M.2 storage slots are listed and the diskless enclosure requires a separate drive budget.
If you choose Synology DiskStation DS425+
- There is no 10GbE upgrade path.
Recommendation switch
The decision flips if...
You want 4GB supplied RAM for a SATA archive
Choose TerraMaster F4-425. F4-425 supplies 4 GB and supports 16 GB while keeping all four SATA bays for the archive. It has no M.2 positions, so an internal SSD plan must use SATA bays.
You want DSM and a supported M.2 storage role
Choose Synology DiskStation DS425+. DS425+ provides DSM and two M.2 positions. Confirm the exact supported SSD and pool role before expecting an SSD mirror alongside four hard drives.
What matters in practice
How to make the call
Start with the required storage layout
The F4-425 includes 4GB memory and straightforward SATA storage. Choose the DS425+ when DSM applications and its two M.2 slots are part of the purchase brief.
Work through the drive budget
Four equal hard drives give the same basic RAID capacity. Do not assign extra archive space to the DS425+ merely because it includes M.2 slots, whose storage-pool compatibility must be checked separately.
Check the actual client and application plan
The F4-425 supports more installed memory, while the DS425+ has Synology-specific SSD compatibility rules. Confirm the exact SSD model and intended caching or storage role before ordering the drives.
What this comparison cannot tell you
- Capacity examples use equal 12TB drives before formatting, snapshots and filesystem overhead.
- Ethernet calculations are lower bounds. Disk performance, network protocol and other traffic add time.
- Memory capacity does not certify application speed or a VM count.
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.
Compared set
Only 8 of 32 models checked match every need here: “Start with four drives” and “Survive one drive failure”.
8 matching models from 32 checkedSee the checked facts and calculation notes
Match countThe count uses the current product-to-need assignments for “Start with four drives” and “Survive one drive failure”. A need with no documented match does not count.
| Product | Needs matched | Checked facts | Source records |
|---|---|---|---|
| TerraMaster F4-425 |
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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.
TerraMaster F4-425
You want 4GB supplied RAM for a SATA archive
See price & reviews on AmazonSynology DiskStation DS425+
You want DSM and a supported M.2 storage role
See price & reviews on AmazonLinks open in a new tab.