Comparison Synology Diskstation DS1819+ vs Synology DiskStation DS1618+

The number of slots for drives in the form factor 3.5", provided in the design of the server.

Initially, 3.5 "is the traditional, most popular form factor of drives for server systems. It is noticeably larger than 2.5", but it allows you to create capacious, inexpensive (in terms of gigabytes) and reliable media, in which it is also easier to implement various additional functions. That is why, specifically in NAS servers, this form factor is also the most popular; slots under 2.5" are much less common in such equipment, and in most cases they complement 3.5".

As for the number of slots, it can vary from 2 (or even 1) in the most basic desktop systems to 8 or more in professional rack-mount solutions. And not only their maximum capacity depends on the specific number of drives, but also some other features of work — first of all, the physical possibility of using one or another RAID level.

This item characterizes the maximum capabilities of the device for connecting drives. This way you can understand how much maximum memory can be added to the NAS server.

Number of M.2 slots provided in the design of the NAS server.

M.2 slot is used for connecting various internal peripheral devices, mainly of a miniature form factor. This solution allows reducing the size of the NAS server itself. Solutions without 2.5" and 3.5" slots can make it compact. It is worth noting that this slot can implement two electrical (logical) interfaces — SATA 3.0 and PCI-Express, with each individual M.2 socket on the board being able to support either both interfaces simultaneously or just one of them. These details should be clarified before purchase, as they directly affect the capabilities of using M.2. For instance, with SATA 3.0 support, such a slot has a significantly lower speed compared to PCI-E; therefore, this M.2 variant is mainly used for inexpensive SSD modules. In turn, PCI-E is somewhat more expensive but provides maximum data transfer speed and allows connecting high-class solid-state drives to the NAS server.

Number of ports USB 3.2 gen1 provided in the design of the NAS server.

USB connectors are used in computer technology for connecting various external peripherals. In the case of NAS servers, this usually refers to external storage devices — flash drives, hard drives, etc. This allows information to be transferred from the internal storage to an external one (for example, for backup purposes) or vice versa, and even to expand the overall working capacity of the server. Additionally, in models with a VGA output (see below), a keyboard can also be connected via USB, and in models with a print server function (see "Software Features"), a printer can be connected accordingly. For added convenience, the USB connector can be placed on the front panel (see below).

Specifically, USB 5Gbps (previously known as USB 3.0 and USB 3.2 gen1) is the direct successor of USB 2.0 and the most widespread USB standard today. This version provides a data transfer speed of up to 4.8 Gbps, as well as fairly high power supply. These connectors are backward compatible with peripherals using USB 2.0.

The maximum amount of RAM that can be installed on the NAS server. It depends, in particular, on the type of memory modules used, as well as on the number of slots for them.

The total number of slots for RAM modules provided in the device; in fact — the maximum number of slats that can be installed simultaneously in this model.

Features for upgrading RAM directly depend on this indicator. So, in low-cost models, there is often only 1 slot, and the only upgrade option is to replace the “native” bar. In more advanced devices, two or even four slots may be provided, while some of them may be free in the initial configuration.

The amount of power consumed by the NAS server during normal operation. Most often, we are talking about maximum power consumption — with all the occupied slots for drives, under high load.

Modern NAS, even high-performance ones, have rather modest power consumption — even among professional models with 10 or more drives, this figure rarely exceeds 1 kW. So there are no problems with connecting to a 230 V network. However, energy consumption information can be useful for some special applications, primarily for estimating the load on UPSs, emergency generators, stabilizers, and other special equipment.

The noise level produced by the device during operation. These data will be useful, first of all, to those who are trying to reduce the noise level as much as possible and, as they say, “fight for every decibel”. However, it is worth noting here that manufacturers can cheat and indicate the noise level for different modes.