Introduction

We would like to thank Synology for supplying the review sample.



Synology's Plus series currently lists eight products tailored around the needs of small and medium business environments. The recently released DS916+ can hold up to nine HDDs with an expansion unit (the DX513), and its quad-core CPU is pretty strong as far as NAS servers are concerned. It can be had with either 2 GB or 8 GB of RAM and is clearly a pro-level NAS. However, if you are an enthusiast and need something powerful for your home, the DS916+ will easily fit the bill. Two Gigabit Ethernet controllers and the CPU's AES-NI hardware encryption engine supposedly allow for transfer speeds in excess of 200 MB/s with even encrypted files, and the CPU's hardware-accelerated transcoding engine allows you to transcode and stream H.264 4K / 1080p content to all your multimedia devices. Please note that Plex currently doesn't support this CPU's hardware transcoding engine, though, so make sure to use Synology's application to stream high resolution and bit rate content since it does exploit the CPU's encoding capabilities.

This NAS only seems to lack an HDMI port. Synology doesn't want to offer this very useful port with its products since it claims that streaming is the only way for a NAS to handle multimedia content. However, an HDMI port isn't only useful in multimedia-specific usage scenarios since it can also be used for local administration. As such, we strongly advice Synology to take another look at this matter to hopefully follow in the footsteps of other NAS vendors who do offer HDMI ports with most of their products.

One of the strongest assets of a Synology NAS is without a doubt the amazing DiskStation Manager, or DSM OS for short. After many years of development, DSM is very mature and stable, offering a plethora of options. You don't need to be an expert to take advantage of its functions and it's very light on resources. Another strong point is its Btrfs and standard ext4 file system support. The ext4 journaling file system is currently the most popular for Linux distributions, but within the last few years, some other file systems with more capabilities have emerged to address some of ext4's shortcomings. One of these fresh filesystems is Btrfs, a copy-on-write filesystem, or "COW", with support for a maximum file size of 16 EiB instead of the 1 EiB in ext4. Btrfs includes other very interesting features like snapshots, pooling, and checksums. One of the most interesting features of Btrfs is snapshot, a special type of subvolume that doesn't make copies of files but shares the data and metadata of the subvolume, which makes it very fast and takes very little space. A Btrfs subvolume's size isn't static since its space is dynamically allocated from the storage pool according to the data that is added or removed. Subvolume creation is also pretty easy, and a subvolume can even have nested subvolumes of its own. By default, there is always a top-level subvolume, which is mounted with all of its own subvolumes, but you can change the default subvolume to allow for a specific subvolume to be mounted without having to mount the subvolume that contains it.

For those of you who didn't understand much of the above, Btrfs offers better data protection than ext4, which is why Synology recommends you format the DS916+'s drives to Btrfs instead of ext4.

Specifications

This NAS uses an Intel Pentium N3710 quad-core CPU with a low 6W TDP, which means there is no need for active cooling on the CPU. The N3710 supports up to 8 GB, and Synology offers the DS916+ in two versions - one has 2 GB RAM and the other has 8 GB RAM. Upgrading the memory of the 2 GB model should you need or want to is possible since the mainboard features a RAM slot.

Up to four HDDs can be installed. Use an DX513 expansion unit and the capacity can be increased to 72 TB before any HDDs are formatted if you use 8 TB HDDs. The two Gigabit Ethernet ports can be teamed for up to 2 Gbit transfer speeds; we believe it is time to offer 10 Gbit ports with even entry-level NAS servers for business environments. The other I/O ports consist of three USB 3.0 ports - of which one is at the face of the NAS - and an eSATA port over which the DX513 can be attached.

The DS916+ can play a significant role in an advanced surveillance system because of Synology's excellent software support. This NAS even supports up to 40 camera channels of which two are free. Another positive is this unit's low power consumption according to data Synology provides, which we will check on with our own equipment.

It isn't large, which is mostly due to the fact that an external power brick is used; speaking of which, it is pretty strong with 100 W maximum power output. In the cooling section, we find two 92mm fans, which is enough to easily keep the HDDs and all other system components cool without it being noisy. Synology also offers a 3-year warranty, which is an additional year over what is usually the case for such high-end NAS servers.



The above table lists all the RAID levels this NAS supports, along with the number of HDDs each takes, and how much redundancy each offers. For sensitive data, we suggest RAID 6 with the second-best option being RAID 5 if you need more storage space and a basic level of data protection.

Packaging

The box doesn't feature a fancy design. On the contrary. it is made of plain cardboard, its only colored parts the two stickers at the front and rear. As long as it provides good protection, which is the case, such packaging is fine with us. Fancy packaging might be a nice touch for high-end VGAs or mainboards, but it definitely isn't a must-have for business-centric NAS servers.


Synology sent us the model with 8 GB of RAM, which a sticker at the rear of the box points to clearly.

Contents & Bundle

Once you open the top flap of the box, you'll be greeted by a message that asks you to check out the HDD compatibility list. Two more links are provided for registering the NAS and getting technical support.


A smaller box contains all the accessories. These are a pair of Ethernet cables, an AC power cord, a set of fixing bolts, a quick start guide, and the power brick.


The power adapter is by EDAC Power Electronics, and its model number is EA11011D-120. It can deliver 8.33 Amps with 12VDC output, or around 100 W of power, which is easily enough to cover the needs of this NAS.

Exterior

The plastic enclosure doesn't look nice since this is an expensive NAS. Plastic also doesn't conduct heat as well as metal. Synology used good quality plastic, but we would definitely prefer a metal case instead, ideally one with a brushed finish.


At the front are several LED indicators, a USB 3.0 port, and the power on/off button.


You have to remove the plastic bay cover to gain access to the HDD trays out of plastic.


We removed the trays to take a photo of the HDD area. As you can see, the fans are installed right behind these trays, which allows them to efficiently rid the HDDs of any heat they produce.


The trays are made of plastic and their quality isn't good enough for such an expensive NAS. The lack of any sound-absorbing material is definitely a downside. In addition, lockable trays are preferable in a business environment.


Synology's logo on both sides also acts as a ventilation grill.


At the bottom of the NAS are four rubber stands, which secure it in place.


Most I/O ports are around the back. You will find a detailed description of them (courtesy of Synology) below.

A Look Inside

It didn't take us long to fully dismantle the NAS since we have lots of experience when it comes to taking apart Synology products. However, the whole procedure can be tricky for many because a good amount of force needs to be applied to remove the covers.


If you are not careful or apply too much force, you can easily break the plastic clips that hold together this two-part chassis.


The mainboard is very small, and the Pentium N3710 CPU is passively cooled thanks to its low TDP of 6 W; it definitely doesn't have to be cooled actively.


The power management IC that control's the CPU's power phases is an IDT P9165. Among others, this IC also includes five integrated, synchronous step-down DC-DC regulators and eleven LDO (Low Drop Out) regulators. We also spotted an IDT P9148 which is probably used for the same purpose, working in parallel with the P9165.


The only components that drew our attention on the solder side of the mainboard are the two Ethernet controllers and the PCIe slots; one is occupied by an SATA expansion board while the other holds a card for the USB 3.0 and eSATA ports.


The RAM slot is occupied by a single DIMM featuring Samsung DDR3 memory chips (K4B4G0846D-XYK0). The voltage regulator that controls its power circuit is a RichTech RT9199.


A Marvell 88SE9215-NAA2 controller is installed on the mainboard. It can handle up to four SATA devices.


The flash memory shown above only contains the part of the DSM operating system used to boot up the system.


An Altera 5M80Z Complex Programmable Logic Device, or CPLD for short, stores the server's configuration.


We found several AP4435GM FETs on the mainboard, which are used by the DC-DC converters that feed various parts with power.


The two USB 3.0 ports in the rear are controlled by an EtronTech EJ168A. We also discovered an eSATA port on the same board; it allows the NAS to be connected to an expansion unit (DX513) for more storage capacity. The same exact board is also used in the DS416, where the eSATA port is covered by the chassis to prevent upgrading this server's capacity through a Synology expansion unit. Synology most likely didn't want to create any internal competition, which meant the DS416's eSATA port had to be removed. Synology apparently only wants to provide the option of adding an expansion unit to their high-end products.


We spotted a PIC16F1829 8-bit micro controller on the mainboard.


Here is a Macronix MX25U6435F Serial Flash module.


A pair of Intel WGI211AT (I211) Intel Ethernet controllers handle the Ethernet ports.


Only high quality polymer caps, provided by Chemi-Con, are used on the mainboard. This is definitely a good sign for this unit's reliability.


The HDD cage holds the NAS server's SATA expansion board.


The two fans are by Y.S Tech, and their model number is FD129225LL-N (92mm, 12V, 0.12A, 1900RPM, 36.3CFM). Their speed is kept low for as long as the unit operates normally, which keeps noise output quite low. According to Y.S Tech, the fans use Sintetico bearings, which look to be of high quality. Y.S Tech says this bearing type to last much longer than a sleeve bearing.