QNAP SilentNAS HS-251+ 2-Bay Passive-Cooled NAS Review

by - 6 years ago




The first NAS that I reviewed after I joined eTeknix was QNAP’s amazing HS-251 NAS, so it is a real pleasure today as I have the upgraded model in the testing area. I will take QNAP’s SilentNAS HS-251+ for a thorough spin in my testing area and check on its performance as well as show you the latest version of the QTS operating system that was released recently.

The HS-251+ NAS retains the same basic design that provides you with a completely silent NAS. There are no fans or other parts that can generate any noise apart from the storage drives you’ll be using. This design adds another bonus which is a dust-free inside. This is made possible because the entire chassis is used as a heatsink for the entire unit and inserted drives. There are no fans to draw dust and other unwanted dirt into the system. That makes it very easy to maintain, but it also means that it should be placed on top of a shelve rather than in a tight spot where it could have trouble getting rid of the excess heat.

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QNAP’s HS-251+ is powered by a quad-core Intel Celeron processor and while some might take a step back here, it’s a great chip for the system. You get four cores that run at 2.0GHz and with a burst speed up to 2.4GHz, it consumes very little power, which also helps with the cooling, and it has more than enough power to drive a system like this. The CPU is backed by 2GB DDR3L RAM and the NAS has a 512MB DOM for the basic system.

Whether you want to mount 2.5-inch or 3.5-inch drives, the HS-251+ can take both. We only got two bays at our disposal here, so most people will probably choose the larger 3.5-inch drives that provide up to 8TB capacity for consumers at the time of writing. Smaller 2.5-inch drives do however run more silently and it produces less heat, so it’s something that is worth to consider in a system like this. The drive bays themselves are hidden behind a removable front that further helps to keep dust out while it also gives the NAS a sleeker appearance.

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Connection wise we find two USB 3.0 ports and two USB 2.0 ports next to the two RJ45 Gigabit Ethernet ports. Sadly none of the ports are located on the front or front end of the sides, but it isn’t a big issue with a flat NAS like this. You can easily both reach and view behind the unit. The NAS supports both printer and storage sharing through the built-in USB ports and over the network, which is a thing that can make the household IT-setup a lot easier.

You can also expand the HS-251+ through the use of QNAPs expansion enclosures UX-800P and UX-500P with 8 and 5 drives respectively. This can provide you with up to 80TB raw storage capacity in the HS-251+ using 8TB drives.

Next to those more normal connections, the QNAP HS-251+ also has an HDMI port from which you can connect it directly to your TV and use it for media playback and even run other operating systems in a virtual environment directly from the NAS. The QNAP QvPC technology is awesome and I’ll be showing you some of those features on the following pages. The HDMI connectivity supports 1080p video playback and the NAS also comes with hardware transcoding capability, making the HS-251+ is an ideal companion at home for multimedia entertainment.


Included with the QNAP HS-251+ is also a remote control that makes the usage from the couch a lot easier, more convenient, and in a fashion one is used to from TVs, DVRs, CD players, etc. With this, it is easy to control the playback and navigate the menus without the hassle of a keyboard and mouse.


The newest QNAP operating system, QTS 4.2, brings an even smoother experience than the predecessors with its flat and modern design. QNAP have streamlined loading times and added an intelligent desktop and multi-window operation that makes controlling every aspect of your HS-251+ fully accessible and easy to use.

It’s easy to centralize your all your files and backups in one place with this NAS, as it allows you to create backup jobs to and from the NAS, sync with computers, tablets, and mobile devices as well as the cloud. The real-time and offline HD video transcoding allows smooth playback of all your files no matter what the connection is like and file formats that might not be supported.

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You naturally also get all the other great features such as the headless 24/7 download center, surveillance station with up to 40 channels, official mobile apps for all key functions and management, app center with official and third-party apps to increase the functionality even more, alert functions via SMS and Email services, web server, FTP server, Radius server, VPN server, print server, Plex media server, and much more.

The QNAP HS-251+ also supports the Qsirch function that is a QNAP exclusive. It is one of the best search function available that will find anything that you’re looking for on your NAS with ease and a lot faster than any traditional method will. Simply type in as much as you know about what you are trying to find, including bits of the file name or even words/phrases in the document, and Qsirch will display a list of matches, complete with thumbnails, as you type.


Feature Highlights

  • Dual-core CPU with hardware encryption engine
  • Your personal cloud with centralized management, file storage, sharing and backup
  • Real-time & offline HD video transcoding for your mobile devices, PCs, and Smart TVs
  • Supports file synchronization between multiple devices to have most up-to-date files
  • Modern set-top design for your digital lifestyle
  • Storage is expandable through extra units

Packaging and Accessories

QNAP’s HS-251+ comes in a plain brown box with a sticker that shows us what is inside. We get all the details we need on the sticker itself, from hardware specifications to features, so it has everything it needs to have.


Next to the NAS itself, we find a Quick Installation guide, the remote control, a power adapter and power cable from the region where it has ben bought as well as two RJ45 LAN cables inside the box.

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A closer look

QNAP wrapped the HS-251+ good and all sides are covered in a protective film when you unpack it. This is a minor thing, but a great one that will make sure that your NAS arrives in perfect condition and stays that way until you get it to where it has to be.

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Once we stripped the protective film from the NAS, we can remove the magnetic front cover and get access to our drive bays. The drives are mounted upside-down compared to what you’d think, but there is a thought behind that. This way the metal drive caddies have direct contact to the top aluminium plate and that in return gives your drives the best possible cooling in such a passive unit.

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The drive trays are easily ejected with the use of the push buttons located between the two bays. Push it to the center and pull out the drive tray. The HS-251+ also supports hot-swapping, in case you wondered.

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When we flip the NAS over, we see four large rubber feet that will prevent vibrations from the drives to be transferred to whatever surface you have placed it on. They also make sure that the NAS has a firm stand and won’t move. The relevant stickers with default information such as MAC addresses and the NAS certifications are also found on the bottom of the unit, leaving the rest clean and minimalistic.


Having a look at the rear of the NAS, we see the power connector and reset button all the way to one side and out of the way from the other connections. The two USB 2.0 ports are placed next to the RJ45 Gigabit LAN ports which again are followed by a Kensington lock in the middle.

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Moving on we see the HDMI port as well as a reserved HDMI port for maintenance. The second one is most likely not one that you’ll ever use and it has a plug to prevent dirt from settling in it while it’s unused. At the end, we find the two USB 3.0 ports as well as the soft-touch power button.

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The drive trays are very simple and consist of a single metal piece with a plastic front. The caddies allow for the use of both 2.5-inch and 3.5-inch drives, giving you the option to pick what you want to use from the massive amounts of available storage drives.

QNAP_HS251p-Photo-drive trays

The NAS is easy to take apart, but it isn’t something you’ll ever need to do. The HS-251+ doesn’t feature upgradeable memory and there is a good reason for that as you’ll see in a bit. The top seen here is actually the bottom and doesn’t hold much besides the two drive tray alignment plates.

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The top is where the actual motherboard is placed and in this NAS it is shaped like a T to make room for everything between the two drives while maintaining the small and compact form factor.

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Now that we have the NAS open, we also see how the drive release mechanism works. It is real simple, but effective.

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Once we remove the motherboard from the chassis, we see the built-in heatsink that connects the CPU directly with the large aluminium top plate which lets it act as a cooler for the NAS. The heatsink is connected with a heat-transfer pad to the CPU itself.


Having removed the motherboard, we see why it doesn’t feature upgradeable memory. There simply isn’t room to place large DIMM or SO-DIMM slots on this motherboard. It is tight as it is.

QNAP_HS251p-PhotoInside-pcb top

QNAP_HS251p-PhotoInside-pcb bottom

The Intel Celeron CPU is soldered onto the motherboard and there are four RAM chips placed next to it. Two on each side of the PCB.


Other chips include ASmedia ASM1074 four port USB3.0 hub controller and two ASmedia AS1442 high-speed TMDS level shift ICs for the HDMI ports, one for each.

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There are also two Intel i210 Gigabit Ethernet controllers on this motherboard, again one for each port.

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The Fintek F71869AD chip provides the NAS with some more sensors and monitoring features among others.

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The system itself has a default USB-based DOM by Apacer as it has been seen a so many NAS before. A proven and reliable system.

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QNAP_HS251p-PhotoInside-dom bottom


System Specifications, Features & Power Consumption

Hardware Specifications


Software Specifications



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The login page is a beautiful one with a fresh design. You can also customize its appearance in the settings once logged in.



QNAP’s dashboard has everything you’ll want. A taskbar at the top with notifications and quick access to vital information, widgets, and customizable icons. Create the setup that fits your needs with ease.


Power Consumption

The chart contains the actual power consumption measured at the PSU connection and while loaded with a maximum amount of drives. Peak, or maximum, power draw will occur during boot times.



Setup – Initialization and Storage Options


There are multiple ways to initialize a QNAP NAS and the included Quick Start guide will help you find the right one for your setup. I prefer to use QNAP’s Qfinder tool that easily finds all QNAP devices on my network and also gives me instant access to various of their settings.


Agreeing to the popup asking to initialize your new NAS or double-clicking it in the list will open the web interface in your default browser.


From here on it’s just a few steps to have your new NAS setup.


The NAS doesn’t need a lot of information to get started, but it does need a few such as a NAS name and a new admin password.


You can choose to set the date and time manually on the device, or you can use the automatic synchronization with NTP servers.


Whether you want to use DHCP to assign a network address and mapping automatically or set them manually comes down to your setup and what you need to do with the NAS. Both are equally valid, but if in doubt, pick DHCP.


Most NAS that I have tested only had Windows sharing enabled by default in the past, so it is really nice to see that we can select which protocols we want to use during the initialization. Most people will only need SAMBA/CIFS for Windows, but there are still a lot of Linux and Mac users out there who need AFP or NFS.

You can also choose to install the most basic and function rich apps right away on the same page and add a lot of extra features to the NAS right away.


We can also pick what disk configuration we would like. The HS-251+ only has two bays, which limits it a little bit. We still had Single, JBOD, RAID 0, and RAID 1 modes available.


The final page of the configuration will show you a summary of your choices and allow you to edit them once more should you want to make some changes. It’s also nice to see the password hidden on this page.


Now you can lean back or go make yourself some coffee as the NAS is applying the settings and configurations you just supplied it with.


You’ll be congratulated to the completion once the setup is done and you can go right from here and directly to the normal user interface.


When we arrive at the QTS dashboard, we’ll be presented with a Quick Start to introduce us to our new NAS and some of its functions. If it has an internet connection available, it will also check for updates to the firmware and operating system right away. In this case the new QTS 4.2 was available and naturally I’ll want to install that.


The update speed is naturally depending on your internet connection and speed, but it didn’t take long for me.


The NAS has to reboot once more when it is done, but you’ll be prompted whether you want to do that now or wait. With a major update like QTS 4.2 is, I would reboot right away and get the new and improved system instead.

QNAP_HS251p-SSinit_old-update finished

After this quick reboot, the QNAP HS-251+ is ready with the brand new QTS 4.2 and all its features. We get a new quick start screen because I didn’t tell it last time to not display it again.

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We also get a prompt whether we want to participate in the QTS Beta program or not. Most normal users will probably not participate while it’s a great option for enthusiasts and developers at the same time.

QNAP_HS251p-SSinit-beta program

Storage Options

There can be multiple reasons to switch the storage setup and luckily QNAP has made the whole thing very easy. You can find the Storage Manager either through the menu from the top left corner or through the normal control panel. Once open, it gives you a quick view on your current storage settings as well the health information and warnings.


You can find more detailed information about the individual drives that are installed in the QNAP HS-251+ as well as run SMART scans too.


There is the option to create and manage all of your storage pools and they’re all listed under each other for quick reference.


The management page will allow you to see the details, which shares are on the volume as well as expand and delete it.


QNAP’s QTS system also offers the ability to use Cache acceleration, but that’s probably not a function that will be used a lot on a livingroom-designed NAS with just two bays. It’s still good to see that it’s there and hasn’t been stripped away.


iSCSI is one of the best ways, in my opinion, to connect your storage. It allows great flexibility and it’s easier to use than most people think.


Externally connected drives can also be viewed through the Storage manager that can provide some basic information and functions for each.


Creating new storage pools and volumes just takes a few clicks and whether you just want to create a pool or do it all at once comes down to how you’re going to use your storage. Novice users should just hit the ‘New Volume’ button.

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You have options between a static single volume as well as thick and thin multiple volumes.

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Select the disks to use and which mode and it’s almost done.

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The final step on creating a new volume defines the size, alert threshold as well as the volume name.

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You can adjust some of the filesystem options, enable full volume encryption, and instantly create a new shared folder at the same time as the volume is created.

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The built-in notification system will keep you up-to-date on the process while it is being created. You can easily move on and do other things while you wait for it to finish.

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Setup – Users, Groups, Shares, and Services


QNAP’s QTS operating system has everything you’ll want when it comes to your users, and they are after all one of the cornerstones on your new. You can view and manage both local and domain users right here.

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Creating a new user presents you with a whole lot of options, but most of them are optional. You need to supply a password and username, but that’s it. You can however also add permission, assign group membership, and set the app privileges too. At the same time your NAS can dispatch an email to the new user and inform him about the creation.

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There’s also the option to create multiple users at once, but that doesn’t offer as many options right away. It does, however, make it a lot easier to create a lot of similarly named users at one time.

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There’s also a function to import and export your entire user list for backup reasons.

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User Groups

User groups is an easy way to manage a lot of users access rights and privileges at once. This can save a lot of time and while it is a basic feature, it is a valuable one.

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The only required information to create a new group is a name, but you can also set a description for easy recognition.

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You can assign already created users right away through an easy checkbox system, which makes it very easy and quick. Should you have a lot of users, then there’s also a search feature.

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Share permission can also be set during the group creation process.

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Shared Folders

You shared folders are another of your NAS’ cornerstones and while a row of default shares have been created by the installed apps, you’ll most likely want to create some more.


The shared folders support advanced folder permission to individual users and user groups as well as folder aggregation.



You get a whole lot of options when creating a new shared folder, but the only required information is a name and the disk volume that it should be created upon. Further settings include manual setting of the path as well as privileges for already existing users.


We previously saw that we could enable full volume encryption when we created our disk setup, but QTS and the HS-251+ also offer encryption for single shares. This will naturally take more resources and be a little slower than a full volume encryption, but how much is something that we’ll see in our benchmarks. It’s a great feature to have for those extra sensitive files that need protection at all costs.

There are a few more advanced settings such as guest access, define it as media folder for the installed apps, and more.


A great feature is the ability to create a shared folder from an ISO image file located on your NAS. It allows easy sharing of backups without having to burn them to a disk first or install extra third-party apps on your workstation.


Network Services

The QNAP HS-251+ is born with pretty much any network file service that you could want and QNAP also added their Qsync Central Station on top of the normal ones.


The Microsoft networking is probably the most used as there are more systems out there running Windows than anything else. We can define the NAS’ network name as well as what workstation it should belong to. AD and LDAP domain membership are also supported.


The advanced options button hides a few more settings such as WINS, NTLMv2, and what the highest used Samba version should be.


The Apple networking page doesn’t have many settings, only to enable the protocol and whether to use DHX2 authentication or not.


The NFS service for Linux users doesn’t have many more options than the Apple page. You can enable it and there’s a link that will take you to the NFS access rights of your network shares.


The QTS operating system comes with a basic FTP service too. It features both standard and encrypted connections and comes with a few settings such as passive FTP range, Unicode support, and maximum user quotas. There is however, sadly, no FXP setting.



Telnet and SSH connections are both supported, but only SSH is turned on by default. This is great as telnet isn’t a secure connection to have open, although very useful at times. SFTP can also be enabled here to increase the connection options.


The Simple Network Management Protocol is an old horse by now, but a great way for system admins to easily stay in control of all their devices.


UPnP will save you from having to set all the port forwards manually in your router. The NAS will take care of anything that is needed for the apps it has running.


A network recycle bin is available globally and it is a great thing to have enabled. Nothing is worse than accidentally deleting a file you need and then realize that it was located on a network drive and therefore not in your normal recycle bin. It’s a great extra backup and security.


The Qsync Central Station allows administrators to manage all Qsync clients in the most convenient way possible. This is a large feature and one that can’t just be shown with these few screenshots.




Setup – There is more, Add-Ons & External Devices

Hardware and Power

The hardware page doesn’t contain as much information as in some other NAS operating systems, but that’s not because it is missing. It is just located elsewhere and we’ll get to that in a little bit. Within the hardware settings here, we find the settings for the physical hardware such as HDD standby times, LED brightness and schedule, as well as the bonus write cache option.

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You can also turn the alarm buzzer on and off for system operations and system events individually.

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The power page has a few tabs, but none of them have a lot of options. While they could have fit on one page, it is nice to have them sorted this way. It makes it quicker to find what you’re looking for. We can enable and disable the EuP mode.

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Enable and disable the Wake on LAN option.

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Set how the NAS should react after a power loss.

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And create power schedules where the system automatically shuts down, restarts, starts, or goes into sleep mode.

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The network settings provide all the settings you could want, from default IPv4 and DNS settings to IPv6, Proxy, DDNS, and more.

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The two LAN ports can also be trunked for those who need faster connections than a single Gigabit Ethernet.

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The NAS is capable of Wi-Fi connections too when used with a compatible USB dongle.

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Personal Cloud and Remote Access

Dynamic DNS services used to be the best way to get remote access to something at home while not having a static external IP address. That feature is still supported, but it might not be the best choice for you.

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The myQNAPcloud feature is much better and not only allows you easy remote connections to your home, it also does all the work for you. You don’t need to configure your router manually nor anything else. All you need to do is login to your QNAP account or create a new one, then give the server a name and that’s it.



System Information

The system information and status pages are quite comprehensive and show the information that wasn’t found under hardware settings.


We get the basic system information first followed by the network status.


The system service pane will show anything that’s running and not running at the same time, giving you a quick view on it all.


The hardware information will tell your CPU speed and usage, memory consumption and temperatures. This is a good page to keep an eye on to begin with as this is a passive cooled NAS. These temps are all well within acceptable margins and shouldn’t have any influence on the hardware performance or lifetime.


The resource monitor gives you a graph view on the performance and usage.


There’s also a process view that can come in handy in when looking for that app that might be stealing all your resources.


Package Center

We have seen quite a few functions already and I’ve only shown a small fraction of what this NAS can do. Should you want more, then you’re in luck as the App Center is full of extra functions and features.


The QTS Essentials are the most used and basic extra features that you’ll be looking for. You’ll find the different QNAP station apps here in a convenient collection.


QNAP also has a list of partners that create apps specifically for the QNAP NAS. You can easily find this in their own category too.


And there are so many more apps to install.

And much more

There still are many more features, but small and large. One of them is the ability to customize the login screen.

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You can get push notifications on connected smart devices as well as emails and SMS

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HybridDesk Station

The last thing I’d like to show on this page is the HybridDesk station that is needed for the HDMI-out to work. Once enabled, you can install a lot of plugins and apps for it as you can see below. This will add all the features you need to the direct usage of this NAS – but more on that on the next page.



Direct Usage via HybridDesk Station

You open up for  a lot of new possibilities with the HybridDesk Station installed and a keyboard, mouse, and monitor connected. It allows you to use the NAS directly as an HTPC replacement – and one that can do more than you’d expect from a NAS.


You can choose which user to login with, which also allows you to set different rights and access on this part of your NAS.


Should you only use it yourself or just use the one user account, then you can also let the HS-251+ auto-login here. This can save you the trouble of entering your password each time. It is however real easy and the included remote is far more receptacle than most TV remotes. The input is swift even when using the limited amount of buttons on the IR remote.


When you are logged in, you’ll see a dashboard much like you’re used to from mobile devices such as smartphones and tablets. Which apps you find here depends on which you installed in your QTS admin panel.


You can naturally also access the QTS admin panel directly from the NAS itself, making the configuration a lot easier. It doesn’t require any extra devices at all.


You can also browse the internet in both Chrome and Firefox. Which sites you visit is naturally up to you, but we would suggest you visit eTeknix.com and read up on the latest tech news and reviews. Big surprise here.



There’s also a dedicated YouTube app where you’ll also find our channel filled with tech news, among them a lot of CES 2016 coverage.


KODI and Plex are two of the most used media systems and both are supported here as well.



You even find Libre Office that allows you to edit and work with all your documents directly on the NAS.


Or perhaps you’ll want to skype with your friends and family? Just connect a USB headset and you should be good to go on this front as well.



Testing Method

Most of the hardware for NAS testing isn’t an important factor when it comes to benchmarks, most of it comes down to the network infrastructure. I will be teaming the two Intel Gigabit Ethernet ports on my test bench and connect them to my managed switch. The same will be done with the available LAN ports on the NAS, which should give a great testing environment.

As part of the testing, the NAS is connected through a D-Link DXS-1210-12TC managed 10GBase switch and then to our test bench to give the best real world setup test that we can and the NAS itself will be packed with Western Digital’s latest RED NAS drives. Intel’s NASPT software does require us to drop the memory down to 2GB, as using any more would lead to data caching and skew the results.

I will be testing the NAS box performance under each of the RAID options that it has available as well just a single drive. Full volume encryption and shared folder encryption will also be tested where available, to check what impact it has on the performance. The USB 3.0 speeds will be measured with our trusted Angelbird SSD2go Pocket drive.


Test system:

Disks in Product:

Network Setup:

We would like to thank our sponsors for supplying us with the components needed for the test system as well as drives.

Software used:

With a device of this sort having so many different applications, Intel’s NASPT software covers all the bases and also gives us a set of results that we will be able to utilize and give a benchmark against other similar systems in the future.

Intel NASPT (Network Attached Storage Performance Toolkit) performs its test by transferring varying sizes and quantities of data to and from the device based on twelve different scenarios.



HD Video Playback

HD Video playback is a read test, where a single 2 Gb file is read in 256 kB blocks sequentially from the drive. This simulates where a 720p HD video is being watched across the network to a media player on the other end.



2x HD Video Playback

2x HD Video Playback works with exactly the same data set as the first HD Video test, however this time the same content is streamed twice from the NAS box simulating two simultaneous streams being made to external media players.

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4x HD Video Playback

In the same way that the 2x Video Playback streams to the equivalent of 2 external media players at the same time, the test here doubles that again up to a simulated 4 media players.

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HD Video Record

The HD Video Record test is, as the name suggests, a write test to the NAS box. A single 2 GB file is written to the device in 256 kB blocks sequentially to the disk.

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HD Playback & Record

The HD playback and record test now put the drive under the same single record and playback tests as before, but now at the same time. This will factor for the quick changes needed to switch between reading and writing two large blocks of data across the network to the device.

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Content Creation

For content creation, Intel have simulated access to via video creation applications. This is made up of 98 files with 12 MB reads and 14 MB writes in varying sizes of blocks. The activity is predominantly non-sequential with the majority of access time made up of writing to the drives. There are quiet periods of read/write activity interrupted with busy periods to present a difficult workload on the drives.



Office Productivity

The office productivity simulation is very similar to the content creation, with a total of 607 files written to and read from the drive. A total of 1.4 GB of data is written to and read from the drive with a close balance between each made – the majority of write access is made up of 1 kB writes.



File Copy To NAS

This test quite simply put copies a single large file from the test system to the NAS box to show how well the system can sustain a single write speed. The 1.4 GB file is copied to the drive and written in 64 kB blocks.

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File Copy From NAS

File copy from the NAS works in exactly the same way as the copy test, but it works in the opposite direction. The single 1.4 GB file is read off the NAS in 64 kB blocks.

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Directory Copy To NAS

In the directory copy to NAS test, a directory tree representing that of a typical commercially available office suite is copied to the NAS to trace the bulk copy of a complex directory. A total of 2833 files making up 247 MB are moved, but the file sizes vary considerably with an average size of 41.4 kB. Due to the varying sizes of the files, only around 50% of the writes are sequential.

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Directory Copy From NAS

In the same way that the file copy from NAS traces the same file back across to the test system, the directory copy from NAS does exactly the same but to the entire directory that it copied across previously.

QNAP_HS251p-Chart-11_dir from nas


Photo Album

Last of all is a test based around a photo album. When a photo album is viewed on-screen, only the images that you see are loaded from the drive and so when you scroll through the album, the new images have to be fetched and read. The album here contains 169 photos with varying file sizes based on the size, quality, and detail in the image. Reading the files in a photo album puts an unusual read load upon the drive as the metadata is read, a thumbnail constructed and finally the image viewed.



Average Throughput

This page shows the average throughput from each of the previous 12 tests in one and it can serve as an easy comparison between products.




Security is an ever-growing concern and encryption is a great step to achieve this. This page will provide a comparison between encrypted data and a normal single drive and what impact it will have on the performance. Not all NAS feature Full volume and Shared Folder encryption, but I will test what is available.

Folder Encryption


Volume Encryption



iSCSI vs. Shared Folder

I’ve also started to include an iSCSI comparison whenever it is available. Windows 7 and forward all have iSCSI initiators built in and the setup only takes a few clicks on your NAS and PCs. It is a convenient and smart way to share storage over your network and its popularity is ever-growing.



Final Thoughts


At the time of writing, the QNAP SilentNAS HS-251+ can he had for $429.00 at NewEgg, £303.90 at Scan UK, or starting from €379.48 through Geizhals.


There is no doubt that the QNAP HS-251+ is a premium NAS in every way. It is also a unique NAS by being such a powerful unit in such a small size and on top of it’s being passive cooled. The plastic cover front hides the drives away and allows the NAS to maintain an overall great appearance. The top aluminium plate is brushed and gives a great look together with the black sides.

The CPU together with the 2GB RAM provide a great base for lots of apps to run at the same time and smooth at that. QNAP also added the QvPC technology to this NAS which allows you to use it directly as an HTPC replacement. This doesn’t just allow you to play media files, but also play games, surf the web, and edit your office documents. The two LAN ports allow for trunking and can also be used separately when needed. The NAS has USB 2.0 that mainly will be used for printers, keyboards, and mice where the USB 3.0 ports are perfect for fast file transfers to and from external storage devices. The NAS sadly doesn’t feature any front accessed ports of one-touch copy button, but that’s due to the design.

The new QTS 4.2 looks amazing and works better than ever. Plenty of features were added and everything seems even simpler to use than before. Whether you need simple network attached storage, a high-end media player, a personal cloud system, a backup target, or more – the HS-251+ can do it.

While it is a premium device and also comes at a premium price, it’s fully worth it in my opinion. It’s also nice to see that the IR remote already is included and that it comes with LAN cables for both ports right out of the box. Minor things, but it’s those things that provide the last bonuses that might tip the user in that direction when they’re making their choice. A device where no corners have been cut is one that you trust.


  • Powerful Intel CPU
  • Dual LAN and USB 3.0
  • HDMI-out and direct usage with mouse and keyboard
  • Great operating system
  • Silent
  • Great design


  • Needs to be placed well ventilated and not in an enclosed space
  • No front USB port and one-touch copy due to the design
  • No eSATA


  • Price

“QNAP’s HS-251+ is probably the best looking NAS for your living room and at the same time it comes with plenty of performance and features that don’t leave many wishes open.”


QNAP SilentNAS HS-251+ 2-Bay Passive-Cooled NAS Review

Thank You QNAP for providing us with this review sample.

Article Index

  1. Introduction
  2. A closer look
  3. System Specifications, Features & Power Consumption
  4. Setup - Initialization and Storage Options
  5. Setup - Users, Groups, Shares, and File Services
  6. Setup - There is more, Add-Ons & External Devices
  7. Direct Usage via HybridDesk Station
  8. Testing Method
  9. HD Video Playback
  10. 2x HD Video Playback
  11. 4x HD Video Playback
  12. HD Video Record
  13. HD Playback & Record
  14. Content Creation
  15. Office Productivity
  16. File Copy to NAS
  17. File Copy from NAS
  18. Directory Copy to NAS
  19. Directory Copy from NAS
  20. Photo Album
  21. Average Throughput
  22. Encryption
  23. Available File Formats and iSCSI
  24. Final Thoughts
  25. View All

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