QNAP TS 251 vs TS 251+

Compared with TS 251, TS 251+ carries a quad-core CPU, shows faster writing speed, and has larger internal memory; however, it has a low-frequency CPU, a slower reading rate, and a higher price.

Lets start off with similarities and differences between both devices:

  • Both these QNAP products are 2-bay network attached systems.
  • Design layout is similar, but TS 251 has white, and TS 251+ has black color.
  • TS 251+incorporates larger internal memory and a quad-core processor.
  • TS 251 has a dual-core processor, but it operates at a higher frequency.
  • Both tools have the same cloud storage, sharing, and backup proficiency.
  • TS 251 presents a higher read speed, while TS 251+ shows a better writing rate.
  • Noise production, durability, and the warranty period are also equal for these two devices.
  • TS 251+ specifies higher buying costs in comparison.

The QNAP TS 251 shows a sleek light-colored look. It carries a high-frequency processing chip, providing better speed for reading functions.

With multiple USB interfaces, it allows connection with USB-enabled drives.

Compatibility with various operating systems makes it useful for such networks where users use different OS devices.

On the other side, the QNAP TS 251+ describes a black outlook with similar features and technical specifications.

The quad-core processor allows it relatively enhanced writing speed. MyQNAPcloud allows a secure, encrypted cloud associated with the NAS that is regularly synced to keep the remote database up-to-date.

Gigabit Ethernet connections provide LAN connectivity, and RAID technology accounts for local disk backup.

Side By Side Comparison:

 TS 251TS 251+
Drive bays22
Drives includedNoneNone  
Drive types3.5’’ SATA HDDs 2.5’’ SATA HDDs 2.5’’ SATA SSDs3.5’’ SATA HDDs 2.5’’ SATA HDDs 2.5’’ SATA SSDs


QNAP TS 251+ takes the winning slot for its better processor and RAM.

It is equipped with a quad-core processor, so it can manage four processing threads simultaneously.

Its RAM is also larger in comparison.

Its 2 GB variant carries 2 chips of 1 GB each, and the 8 GB variant carries 2 chips of 4 GB each.

However, its operating frequency is slightly lesser than its competitor.

On the other side, QNAP TS 251 carries a reliable but relatively less efficient CPU and smaller RAM.

Its processing unit is dual-core only and allows the management of just two information threads at a time.

It has a 1 GB variant with a single memory chip and a 4 GB variant with 2 memory chips of 2 GB each.

Its frequency is relatively higher, though.

 TS 251TS 251+
ProcessorIntel Celeron dual-core 2.58GHzIntel Celeron J1900 Quad-core 2.0GHz bursts up to 2.42GHz
Internal memory1GB DDR3L or
4GB DDR3L or
Processing frequency2.58GHz2.0GHz bursts up to 2.42GHz


QNAP TS 251+ takes the lead for writing functions as its quad-core processor leads to better writing speed, and sequential throughputs further improve its performance.

However, it shows comparatively slower read functions owing to its minor frequency.

Conversely, the writing efficiency of QNAP TS 251 is lower than its competitor because its dual-core unit takes longer to encode new information.

Nonetheless, its reading speed is higher due to its better processing frequency.

Its CPU operates quickly in comparison, ensuring faster responses.

 TS 251TS 251+
Processing frequency2.58GHz2.0GHz bursts up to 2.42GHz
Reading speed (Mbps)224 (sequential throughput) 128 (encrypted transmission)223 (sequential throughput) 205 (encrypted transmission)
Writing speed (Mbps)222 (sequential throughput) 95.7 (encrypted transmission)225 (sequential throughput) 178 (encrypted transmission)


QNAP TS 251 is a white, tower-form NAS showing a contemporary, sleek, and minimalistic outlook.

It is a 2-bay device with hot-swappable drives accessible from the front side.

Besides that, a marginal bar carries power and copy buttons, a USB port, and status indicators.

The rest of the elements like USB ports, Ethernet RJ-45 ports, security slot, fans, and power slot are present on its rear side.

TS 251+ has an identical layout but in black color.

Its weight and dimensions are also very similar. It also enables dual LAN connectivity because it carries two RJ-45 Gbe ports.

These devices also score the same for endurance against extreme temperatures and humidity.

 TS 251TS 251+
Dimensions (H x W x D)169 x 102 x 219 mm168.5 x 102 x 225 mm
Weight1.28 kg1.28 kg
USB ports2 x USB 3.0 ports 2 x USB 2.0 ports2 x USB 3.0 ports 2 x USB 2.0 ports

Product variants

TS 251 comes in two space variants carrying memory chips of different capacities. One of these variants has 1 GB, and the other has 4 GB(2×2 GB) RAM.

In comparison, QNAP 251+ also has 2 space variants.

The model with smaller RAM specifies 4 GB internal memory (2×2 GB), while the other variant carries 8 GB internal storage (2×4 GB).

Cloud storage

These devices are linked with MyQNAPcloud, allowing remote storage, regular synchronization, and cross-platform sharing.

Qsync keeps the database updated for all associated network users.

You can access your private cloud remotely via different QNAP apps.

These systems also enable mutual sharing and syncing with various commercial cloud services.

These public platforms include Google Drive, Dropbox, Microsoft OneDrive, Yandex Disk, Amazon Cloud Drive, Amazon S3, Amazon Glacier, Microsoft Azure, and Elephantdrive.

Backup and Sharing

Both these NAS enable their users to collaborate on projects and share files with other network users effortlessly because they permit many user accounts and groups.

Moreover, many FTP concurrent connections ensure access for all group members when working on the same files.

Similarly, these QNAP products show equal backup efficiency.

They have a one-touch-copy function that creates a local backup by mirroring all files from one disk to the other.

Snapshot replication ensures the accuracy of these backup files.

Remote backup mechanisms provide multiple options for data recovery.

Hybrid backup Sync, NetBak replicator, and Real-time remote replication (RTRR) automatically backup NAS data on the remote database, providing full data recovery in case of any loss.

 TS 251TS 251+
RAID levelsJBOD, Single, RAID 0, 1JBOD, Single, RAID 0, 1
Snapshots replicationPP
Local users accounts40964096
Local group accounts512512
Maximum FTP connections10241024
HBS backup jobs400400


The setup process for these gadgets is easy and simple because you can conveniently slide the drive tray out for disk installation without the hassle of disassembling your device.

After mounting the hard disk, follow the tutorial given in the user manual to install and configure QTS from the QNAP web portal.


Both TS systems rank at the same position for noise production as their system fans have the same dimensions and speed.

Both carry 1 cooling fan of 70 mm that works on quiet mode.

That is why the noise level of these devices is lower than most 2-bay network-attached systems.

 TS 251TS 251+
Fan dimensions70 mm, 12V DC70 mm, 12V DC
Noise rating15.4 dB15.4 dB


Both these NAS are durable because they have established Intel CPU, tough hardware casing, and reliable QTS operating system.

QNAP backs these TS products with a limited warranty spanning 2 years from purchase. Moreover, you can get a longer warranty for further 3 years by paying an additional amount.


TS 251 ranks economically favorable due to its lower price. It offers reliable cloud networking facilities and faster read speed within a reasonable price range.

In contrast, QNAP TS 251+ comes at a higher cost because it carries a better processing chip, RAM, and faster writing speed.