It’s offers a high-end spec for a home NAS, powered by an Intel Celeron N3060 dual-core processor running at 1.6GHz, with boost speeds up to 2.48GHz. That performance is there for a reason – it claims to offer 4K playback and decoding on the fly, so you can watch high-quality files on your TV smoothly. We’ll find out if that’s true. 

QNAP TS 251A review: Design and features 

At the rear are two USB 3.0 ports and two Gigabit Ethernet sockets. There’s also an HDMI port at the rear, so you can even hook the QNAP up directly to a TV and watch content direct from the drive on it. And if your network is down for any reason you can also plug in a mouse and keyboard and operate the NAS directly, like you would with a conventional computer. A remote control is supplied, suitable for basic operations.  There are two USB 3.0 ports on the front but one of these is an unusual micro B connection. This is for hooking up to an external drive, so you can backup or copy content from or to the drive. This seems an unusual option to have, but has been designed so that you can back up your files without having to worry about the network. Bizarrely though, the necessary cable isn’t included in the box, but you can pick one up for a fiver, so it’s not the end of the world. An SD card slot is also available so you can suck the photos from your DSLR straight onto the NAS.  The drive bays slide out easily but installation is not tool-less – getting the disks in will require the use of a screwdriver. Once done you turn on the drive and it’s hooked up via Ethernet you should, in theory, be able to set it up via a ‘Cloud Installation’ – whereby you scan a QR code with a reader app on your mobile and the drive will be identified and set itself up. This didn’t work smoothly for us as it didn’t detect the drive, so we went with a more traditional approach. We downloaded and installed the QFinder Pro utility to our Mac and using this the drive was duly detected and the latest firmware installed. In fact, you’ll need this utility installed to be able to make use of the USB 3.0 micro B port on the front for hooking up an external drive. See all NAS drive reviews

QNAP TS 251A review: Software 

Once set up, and you login to your NAS via a browser you’ll discover the TS-251A to be powered by one of the most comprehensive NAS OSs on the market. The simple icon and window based interface is speedy and easy to use. QTS offers a huge range of apps available to install. There are staples such as a Photo Station, Music Station, and a Download Station, from which you can search for P2P files without having to use a PC. There’s also a wealth of choice in the App Center with a wide range of categories, from surveillance apps, to software that enables you to run a WordPress site to an email server.  There is also a Video Station app, but this has no support for MKVs, which means it won’t be much use to many. Of all the apps available the one that interested me most was Plex, the media organisation software. Interestingly, you can run both the Plex Media Server and the Plex client on the same box. It works very well and with the QNAP attached to the TV I was able to browse and play content using the supplied remote control. You can also access it via a Plex client on an Xbox One or PS4.  One issue we found was the noise level. Our drive was filled by two Seagate ST8000VN0002 8TB drives setup in RAID one. This proved to be noisier in operation than we would have liked, and at times emitted a slightly irritating vibration noise. This could be corrected if we slightly moved the unit, but it was a pain to have to do so. The unit was certainly louder than a four disk Synology unit that we’ve had running since 2008. 

QNAP TS 251A review: Performance 

To test performance, we used CrystalDiskMark and with a 1GB sequential test with saw read performance of 111MB/s and write performance of 118.5MB/s – very impressive indeed. You won’t be wanting for performance from this drive. See all storage reviews To test the port on the front we hooked up to a Macbook Pro laptop and using BlackMagic Disk Test we saw speeds of 106 MB/s write and 107 MB/s read – very good indeed.