The TerraMaster F4-423 is touted as a high-performance NAS enclosure for SMB. This positions the F4-423 against competitor enclosures like the Synology DiskStation DS920+. TerraMaster has been best known for producing some excellent value NAS that undercut the competition in both specs and price, but all that’s about the change with the F4-423.

Replacing the TerraMaster F4-421, gone is the weaker J-series Celeron processor, DDR3 RAM, and terrible TOS operating system. Actually, the OS remains the same, but we’re now at TOS version 5 and it’s vastly improved, though still a little rough compared to Synology, QNAP, and ASUSTOR. Still, TerraMaster is pulling out all the guns with this NAS.
I’ve rated TerraMaster NAS as some of the best value enclosures out there, in all segments of the NAS market. Read on to find out if I’m swayed enough to include the new TerraMaster F4-423 as one of the best NAS for the home and office.

TerraMaster F4-423
TerraMaster is bringing some serious power to its value-focused mid-range NAS enclosure family. You’ll find some more advanced features here usually reserved for premium servers.
- Great value
- Four drive bays
- Powerful Intel Celeron CPU
- M.2 slots and 2.5Gb LAN
- Upgradable RAM (max 32GB)
- OS is still a little rough
- No expansion support
- Awkward access to M.2 and RAM slots
Price and availability

The TerraMaster F4-423 launched with an MSRP of $500. This puts it in the same ballpark as the Synology DiskStation DS920+, a NAS that’s best suited for running Plex Media Server. The outgoing F4-421 was priced at $470 at launch, so for an extra $30, TerraMaster is including some serious upgrades.
Specification | TerraMaster F4-423 |
---|---|
Processor | Intel Celeron N5105/N5095 |
GPU | Intel UHD Graphics |
RAM | 4GB DDR4 (32GB) |
Drive bays | 4x (SSD/HDD) 2x M.2 (NVMe PCIe 3.0) |
Capacity | 80TB |
Expansion | – |
Cooling | 2x 80mm |
Ports | 2x Rear USB-A 3.2 Gen 2 1x HDMI 2x 2.5Gb LAN |
Power draw | ~ 35.2W |
Dimensions | 227 x 225x 136 mm |
Weight | 2.3 kg |
We received the F4-423 for review from TerraMaster without any hard drives, allowing us to perform our own testing methodology to maintain consistency.
TerraMaster F4-423: What you’ll love

I was interested to learn what TerraMaster changed with the successor to the F4-421. I was a fan of that enclosure for the value it offered, but it fell short when compared to the competition. This isn’t the case with the F4-423.
TerraMaster made some serious component upgrades for the F4-423 to create one powerful four-bay NAS.
According to TerraMaster, the company managed to achieve a 50% overall system performance boost, compared to the aging F4-421. Then there’s a 37% increase in file and photo retrieval speeds, a 35% increase in database response speeds, and a 40% increase in webpage PHP response speeds.
How TerraMaster was able to boast these figures is largely down to the internal component upgrades. The Celeron J-series processor has been swapped out for an N-series Celeron. Then there’s the DDR4 RAM, which can be upgraded to two 16GB modules for a capacity of 32GB. Next up are the two 2.5Gb LAN ports.
All of this thrown inside a well-designed metal chassis makes for quite the compelling NAS enclosure. The four drive bays are capable of handling 20TB drives, opening up a maximum capacity of 80TB. Should faster access be required, SSDs can be used but at additional cost (and lower capacities).



On the front of the TerraMaster F4-423 are the four drive bays for 2.5-inch SSDs or 3.5-inch HDDs. There’s a power button and a few LED indicators for network and drive activity. The sides have TerraMaster branding and the top of the NAS is completely bare.
The rear of the F4-423 plays host to the two USB-A 3.2 Gen 2 ports, two 2.5Gb LAN ports, and a single HDMI output. The latter feature is a fantastic addition for those who enjoy using Plex Media Server to stream content to the big screen. Directly connecting this NAS to your TV allows it to perform other tasks instead of transcoding.
The two 2.5Gb LAN ports are fantastic, especially if you’re rocking flash storage. Even with mechanical drives, you’re going to have a good time with a capable network that can handle such speeds. You can expect transfer rates of 270MB/s (and beyond) with a single connection or somewhere in the region of 5Gb when link aggregation is enabled and multiple clients are accessing the NAS.
I tested the TerraMaster F4-423 with two 16TB Seagate IronWolf drives and found no issues with the experience. Configuring RAID was painless and running tests showed speeds that weren’t far off what TerraMaster claims in marketing materials.
TerraMaster F4-423: What you’ll hate

I’m stumped when it came to the TerraMaster F4-423 as there’s not really anything I disliked about the NAS. It ticks all the right boxes for a mid-tier enclosure, including a powerful Intel processor, speedy networking, SSD caching support, and a colossal amount of DDR4 RAM.
TOS, the operating system (not the terms of service), has been refreshed to give it a slightly more modern look and it’s certainly more responsive on the F4-423. I couldn’t help but still find the OS a little lacking compared to what QNAP, Synology, and ASUSTOR offer. It’s almost there.


The main issue I have is with access to the M.2 and RAM slots. You have to take apart the enclosure to pull the PCB and drive trays through the rear. It’s not terribly complicated and takes a few moments of your time, but it’s simply not as user-friendly as some other enclosures.
TerraMaster F4-423: Competition

The TerraMaster F4-423 is no longer a value enclosure you’d consider for price alone. Even when put up against serious competition like the excellent Synology DiskStation DS920+, it handles its own on the specs sheet alone. The below table showcases what TerraMaster has included to shake up the market.
Specification | TerraMaster F4-423 | Synology DiskStation DS920+ |
---|---|---|
Processor | Intel Celeron N5105/N5095 | Intel Celeron J4125 |
GPU | Intel UHD Graphics | Intel UHD Graphics 600 |
RAM | 4GB DDR4 (max 32GB) | 4GB DDR4 RAM (max 8GB) |
Drive bays | 4x (SSD/HDD) 2x M.2 (NVMe PCIe 3.0) | 4x (SSD/HDD) 2x M.2 (NVMe PCIe 3.0) |
Capacity | 80TB | 72TB |
Expansion | – | Yes (DX517) |
Cooling | 2x 80mm | 2x 92mm |
Ports | 2x USB-A 3.2 Gen 2 1x HDMI 2x 2.5Gb LAN | 2x USB-A 3.2 Gen 1 1x eSATA 2x 1Gb LAN |
Power draw | ~ 35.2W | ~ 32.2W |
Dimensions | 227 x 225x 136 mm | 166 x 199 x 223 mm |
Weight | 2.3 kg | 2.24 kg |
The processor is a considerable upgrade, and so is the DDR4 RAM, which can be bumped to a whopping 32GB with full support from TerraMaster. Then there’s the 80TB capacity with the four drive bays and two 2.5Gb LAN ports. If you’re wanting a NAS to store and transfer large files, or run intensive applications and services, the F4-423 is a good choice.
If all that wasn’t enough already, the two M.2 slots will allow one to install NVMe SSDs for use as a cache. This was previously reserved for more expensive enclosures and it wasn’t on the TerraMaster F4-421, giving the F4-423 a new party trick. It’s a serious NAS enclosure for serious people.
Should you buy this NAS?

Who should buy this?
- If you want a good value 4-bay NAS.
- If you need a NAS with four drive bays.
- If you want more advanced features.
- If you want to run Plex Media Server.
Who shouldn’t buy this?
- If you need to store more than 80TB of data.
- If you want to enjoy advanced cloud-based features
- If you don’t need more than two drive bays.
Shipping around for a good value four-bay NAS enclosure? You just found the perfect solution in the form of the TerraMaster F4-423. The company has thrown some serious features inside this chassis, allowing it to go up against considerably more expensive enclosures.
Whether you plan on running a Plex server for media streaming, want to run a website, or throw up a few virtual machines, you’ll have a great time with this NAS. The OS has come a long way with TOS version 5, but there’s still some work to be done to bring it up to speed with the competition.
For the price, this is easily one of the best value enclosures for the mid-range NAS segment.

TerraMaster F4-423
TerraMaster’s F4-423 NAS enclosure is incredibly powerful for home use. Whether you plan to host a website, save surveillance footage, stream media, or all of the above, the F4-423 will handle it without issue.