First home/SOHO Intel dual-core NAS with a PCIe slot for extending NAS functionality
The TS-251B combines secure data storage and multimedia entertainment into one device. Featuring a PCIe slot, the TS-251B is QNAP’s first home/SOHO NAS that allows you to flexibly extend its functionality and potential applications. You can install a QNAP QM2 card to provide M.2 SSD caching/10GbE connectivity and use with Qtier auto-tiering storage to enhance overall system performance; or install a wireless network card (such as the QNAP QWA-AC2600) to turn the TS-251B into a wireless access point and to wirelessly stream your multimedia throughout your home. The TS-251B supports dual-channel H.264 hardware decoding and transcoding, allowing you to enjoy watching NAS media files smoothly across various devices.
The PCIe port supports installing a 10GbE network card, a QM2 dual-port M.2 SSD/10GbE card, a USB 3.1 Gen 2 (10Gbps) card, or a wireless network card.
4K media playback and online transcoding; cross-device multimedia viewing via HDMI output or streaming applications.
Snapshots fully record the system status and data. If files are accidentally deleted or modified, you can quickly restore the previously-recorded data.
Hybrid Backup Sync consolidates backup and sync tasks into a single app, providing multiple layers of data protection.
Remotely access the apps and files on your TS-251B via myQNAPcloud and easily manage and share files.
Supports containerized applications and hosting virtual machines with various operating systems.
TS-251B-2G - Intel® Celeron® J3355 dual-core 2.0 GHz processor (burst up to 2.5 GHz) with 2GB RAM (1 x 2GB)
TS-251B-4G - Intel® Celeron® J3355 dual-core 2.0 GHz processor (burst up to 2.5 GHz) with 4GB RAM (1 x 4GB)
Intel® Celeron® J3355 dual-core processor and AES-NI hardware encryption
Powered by a 14nm Intel® Celeron® J3355 dual-core 2.0GHz processor (burst up to 2.5 GHz), 2GB/4GB DDR3L RAM (up to 8GB), a single Gigabit LAN port, and supporting SATA 6Gb/s hard drives, the TS-251B provides dependable performance of up to 672 MB/s read/write speeds. The TS-251B features Intel® AES-NI hardware-accelerated encryption for both full NAS volumes and shared folders, boosting system performance while ensuring the security of sensitive data stored in the TS-251B.
Extend NAS functionality with the PCIe slot
With a PCIe expansion slot, the TS-251B provides flexibility in extending NAS functionality and potential applications. Install a QNAP QM2 card to provide M.2 SSD caching/10GbE connectivity and use with Qtier tiered storage for optimal system performance; use the TS-251B as a wireless access point by installing a compatible wireless network card (such as the QNAP QWA-AC2600) to create a wireless media streaming environment; or boost the USB connectivity of the TS-251B by installing a USB 3.1 Gen 2 (10Gbps) card.
Upgrade your network to 10GbE with QNAP's fast and affordable 10GbE Switch
QNAP 10GbE/NBASE-T™ unmanaged switches allow you to instantly upgrade your network environment at a cost-effective price. With a 10GbE network you can enjoy blazing-fast transfer speeds, empower bandwidth-demanding tasks like virtualization, and enable simultaneous real-time access to large NAS-based files using multiple workstations (ideal for video editing and multimedia). QNAP also provides a 10GbE PCIe network expansion card for the TS-251B and Windows®/Linux® PCs to take advantage of high-speed LAN environments.
Real-time 4K video transcoding
Featuring advanced Intel® HD Graphics, the TS-251B supports dual-channel 4K H.264 hardware decoding and real-time transcoding, allowing you to convert videos to universal file formats that can be smoothly played across various devices*. You can also watch high-quality 4K@30FPS media files on a HDTV using the HDMI output or use with Plex® Media Server to stream media files to mobiles devices and media streaming devices (including DLNA®, Roku®, Apple TV®, Amazon Fire TV® and Chromecast™). The QNAP RM-IR004 remote control (sold separately) can be configured using QButton to customize the actions of individual buttons, providing a more convenient NAS experience.
*The TS-251B’s hardware provides H.264 hardware decoding, encoding and transcoding capabilities. However, playback quality may vary due to factors including playback software, file formats, system usage, and available bandwidth.
Multiple ways to enjoy your multimedia
QNAP provides a wide range of multimedia applications for you to easily enjoy photos, music, and videos.
Cinema28 allows for single-interface management of all your media files and can stream files to every connected device throughout your home.
QVHelper allows users to stream media files or music playlists from a QNAP NAS to VLC player.
Qmedia allows music, photos and videos to be effortlessly streamed to Android TVs or set-top boxes.
Video HD is a free KODI add-on that combines KODI's streaming and video decoding capabilities and fully supports Video Station's features.
Protect important data with snapshots
Snapshots help protect your data by fully recording the NAS system state and metadata. If files are accidentally deleted or modified or the system is afflicted by ransomware, you can use snapshots to quickly restore files to a previously-recorded state. QNAP snapshots are block-based and only record the changed data. Not only does this save storage space but also reduces the time required to back up and restore data. The TS-251B supports up to 1,024 snapshots per NAS and up to 256 snapshots per volume or LUN.
Automate everyday tasks with IFTTT Agent
QNAP IFTTT Agent integrates the popular web automation service IFTTT (If This Then That), allowing you to create a near-unlimited number of automated workflows. Simply connect your IFTTT account with your TS-251B and set triggers and actions. For example, if you set a trigger as “Any new photo on the phone” and the action as "Upload the photo to QNAP NAS," then all the photos taken using your phone will be automatically uploaded to TS-251B.
Multiply your productivity
The app-driven QTS operating system provides solutions for simplifying file backup, management, search, and more. With File Station you can view and manage your files from NAS and multiple storage devices; the OCR Converter allows you to extract text from images; Qfiling helps automate file organization, and Qsirch helps quickly find files.
Centralized File Management
Use File Station to directly access files on USB devices - including optical disc drives. Files from different devices can be easily viewed and managed on a single interface.
OCR Converter extracts text from images, helping to boost productivity and making it easier to find files.
Qfiling automates file organization. Files are automatically archived into folders based on your settings.
Qsirch quickly finds images, music, videos, documents, emails, and other files.
Multi-point file backup, access and sync
The TS-251B centrally stores data and files, and supports SMB/CIFS, AFP and NFS protocols for file sharing across Windows®, Mac®, and Linux®/UNIX® devices. Coupled with Qsync (a utility that turns a QNAP NAS into a safe, high-capacity data center for file synchronization) any file uploaded to the TS-251B will be made available for all linked devices, such as computers, laptops and mobile devices. Hybrid Backup Sync can help you easily backup or synchronize data on the TS-251B to other QNAP NAS, remote servers, or cloud storage for easy disaster recovery.
QVR Pro safeguards your environment
QNAP’s QVR Pro surveillance solution allows you to arrange a dedicated, independent storage space for surveillance data on TS-251B and leverage the advantages of scalable storage. With QVR Pro, camera management, storage space allocation, camera live view, and playback is greatly simplified. You can also use USB webcams as network cameras with the QUSBCam2 app, and remotely monitor your surveillance feeds at any time with QVR Pro Client’s companion mobile app.
NAS as a Multi-OS Platform
Virtualization Station and Container Station provide comprehensive solutions for creating virtualized environments to improve business IT infrastructure, workflows, and productivity.
Virtualization Station allows you to run multiple Windows®, Linux®, UNIX® and Android™ virtual machines on the TS-251B. You can use Virtual Network Computing (VNC) through a browser to operate the virtual machines. Virtualization Station is ideal for organizations to run multiple applications on a single NAS.
Container Station integrates LXC and Docker® lightweight virtualization technologies. You can download apps from the built-in Docker Hub® to easily import/export container apps and manage access controls, enjoying the benefits of easy installation, transferability and high-efficiency.
Flexible and economical storage expansion
You need an easy solution to increase storage capacity when running out of space. QNAP provides several ways to expand your NAS storage as needed to accommodate data and business growth.
Upgrade RAID Capacity
Hot swap lower-capacity drives with larger-capacity drives so that your QNAP NAS can grow with your business.
Use VJBOD (Virtual JBOD) to expand your storage capacity by using the unused storage of other QNAP NAS. Up to 8 QNAP NAS can be mounted as local disks on the TS-251B.
Attach Expansion Enclosures
Connect two 2-bay TR-002 or 4-bay TR-004 USB hardware RAID external enclosures* and use the Storage & Snapshots Manager to easily handle NAS capacity expansion.
*TR-002 and TR-004 will be available soon.
Intel® Celeron® J3355 dual-core 2.0 GHz processor (burst up to 2.5 GHz)
Architecture: 64-bit x86
Intel® HD Graphics 500
2 GB DDR3L (1 x 2 GB)
4 GB DDR3L (1 x 4 GB)
8 GB (2 x 4 GB)
2 x SODIMM DDR3L up to 1866, with dual-channel support
2 x 3.5" SATA 6 Gbps HDD
• 3.5" SATA 6Gb/s HDD
• 2.5" SATA 6Gb/s HDD
• 2.5" SATA 6Gb/s SSD
SSD Cache Acceleration Support
3.5" drive bay：1 to 2
Gigabit Ethernet Port
1 x RJ45
2 x USB 3.0, 3 x USB 2.0
USB One Touch Copy
Front：USB 3.0 Type-A
1 PCIe 2.0 x2 slot
1 x HDMI v1.4b (up to 3840 x 2160 resolution at 30 Hz)
, supporting QNAP RM-IR004 remote control (optional purchase)
1 x speaker, 2 x MIC Input
1 x 3.5 mm line-out jack
Note: You cannot use the speakers and the line-out jack simultaneously.
Status/power、LAN、USB、HDD 1 - 2
Power, Reset, USB One-touch-copy
Alarm buzzer and voice prompts
Dimensions (H x W x D)
168 x 105 x 226 mm ( 6.61 x 4.13 x 8.90 inch)
1.53 kg (3.37 lbs)
Power Consumption (W)
HDD standby：8.08 W
In operation：15.25 W
(with 2 x 1TB HDDs installed)
Sound pressure (LpAm): 17.3 dB(A)
Power Supply Unit
65W AC adapter, 100-240V
1 x 7 cm
Operating Temperature & Relative Humidity
0 ~ 40˚C ( 32˚F ~ 104˚F ), 5 ~ 95% RH non-condensing, wet bulb: 27˚C (80.6˚F)
Kensington security slot
Note: Use only QNAP memory modules to maintain system performance and stability. For NAS devices with more than one memory slot, use QNAP modules with identical specifications. Warning: Using unsupported modules may degrade performance, cause errors, or prevent the operating system from starting.
* Sound Level Test Environment: Refer to ISO 7779; Maximum HDD loaded; Bystander Position; Average data from 1 meter in front of operating NAS.
Designs and specifications are subject to change without notice.
| Stock code || IBQ-251B-4G|
| Brand || Qnap|
| Series || Desktop NAS|
| Model || TS-251B-4G|
| Type || 2-Bay RAID (4GB RAM) + PCIe|
| ROHS || Y|
| Date added || 13/06/2018|
TS-251B-4G Spec Information
| Form Factor / Drive Height || 168x105x226mm|
| Platter size || 3.5"|
| Platter (alternate) || 2.5"|
| RAM/Cache || 4GB|
| Guarantee || 2yr|
| Processor || Intel® Celeron® J3355 dual-core 2.0 GHz processor (burst up to 2.5 GHz)|
| CPU Mark (cpubenchmark.net) || 1325|
| Total Drives || 2|
| RAID || 0:1:JBOD:|
| RAID Levels || Single Disk, JBOD, RAID 0, 1|
TS-251B-4G Spec Connections
|SATA||SATA 7-pin Discrete with Power||Internal||2|
|PCIe||PCIe v2 x2||Internal||1|
|USB3||USB3 type A (host)||External||2|
|USB2||USB2 type A (host)||External||3|
| Speed/RPM || 6Gb/s to Gigabit Ethernet (1,000 Mbit/s)|
| Weight (kg) || 2.7kg|
| Weight (bare) || 1.53kg|
| External Length (mm) || 390cm|
| External Width (mm) || 320cm|
| External Height (mm) || 300cm|
| Colour || White|
Qnap Desktop NAS TS-231P3-8G 2-Bay RAID (8GB RAM) + 2.5G |
Qnap Desktop NAS TS-251D-8G 2-Bay RAID (8GB RAM) + PCIe |
Qnap Desktop NAS TS-251D-16G 2-Bay RAID (16GB RAM) + PCIe |
Qnap Desktop NAS TS-253Be-8G 2-Bay RAID (8GB RAM) |
Qnap Desktop NAS TS-431P3-8G 4-Bay RAID (8GB RAM) + 2.5G |