Comparison Ugreen CM198 vs Ugreen 50423

General type of enclosure for storage drives. Nowadays, these devices are mainly divided into external and internal, but there are also more specific varieties, such as docking stations and cases. Here is a detailed description of each option:

— External. Models used outside the cases of PCs/laptops, designed to convert internal drives into external ones. Enclosures of this type perform two main functions. Firstly, they allow connecting HDDs and SSDs with an "internal" interface, such as SATA, to an external port, most often USB. Secondly, the enclosure provides convenience in storage and transportation and offers additional protection to the contents from dust, moisture, and other adverse factors. Such a device can be useful, for example, on a business trip where you need to carry a lot of work materials: you can remove the hard drive entirely from the computer and keep it with you, using it as an external drive. Another application example is a working HDD or SSD left over from an old system that is not needed inside a new computer: such a drive with an external enclosure can be a good (and definitely cheaper) alternative to a new device solely for external use.
Note that although most enclosures of this type are portable, there are also stationary models; see "Purpose" for more details.

— Internal. Enclosures des...igned for installation inside the case of a PC, laptop, or server. They can perform different functions depending on their specialization (see "Purpose" for more details). For instance, in laptops, enclosures are used to install internal drives in non-native slots. In PCs and servers, the specificity of such devices is somewhat different—they are often used to enable quick transfer of drives from one case to another. However, there are also solutions that function as adapters—specifically, for installing 2.5" drives in 3.5" slots and for connecting M.2 format SSD modules in PCI-E slots for expansion cards. Note that the drive interface in internal models usually corresponds to the connection interface (see below)—simply put, the same interface is used to connect the drive to the enclosure and to connect the enclosure with the installed drive to the computer. But again, exceptions can occur—such as the mentioned M.2-PCIe adapters.

— Docking Station. A special variety of external enclosures mainly intended for stationary use. The main difference between "docks" and regular external enclosures is that instead of full compartments for drives, only bays for connection are provided—in the form of indentations with connectors. Thus, drives are installed on the docking station like on a stand, and in such a setup, they remain almost completely open. The main advantage of this design is maximum simplicity and speed of replacement; therefore, it makes sense to use docks in cases where frequent changes of installed HDDs/SSDs are needed. One example of such use is professional diagnostics of internal drives: instead of constantly placing each "patient" directly in the case or in a traditional external enclosure, it's easier to use a dock. Also, note that docking stations often provide several slots for drives at once, and individual slots may have the ability to be reconfigured for different form factors (see "Drive Slot" for more details).

— Case. Standard cases for carrying drives; they serve no other function beyond storing the contents and protecting them from dust, moisture, and other adverse factors. As a rule, cases resist dirt well, but their shock resistance may vary, and it is most often low—if this aspect is important to you, it is worth clarifying separately.

The number of separate slots for drives provided in the design of the pocket, in other words, the number of drives for which this model is designed.

In addition to models for one slot, nowadays you can find more capacious solutions — for two drives, or even more. Such "multiplying" is found in three types of devices. The first is large-format pockets for stationary purposes (see above), operating in the format of separate storages for a large amount of data. Such models may support RAID arrays (see above) and other special features. The second type of devices with more than one slot are separate docking stations (see "Type") with similar functionality. The third type is server models (see "Purpose") with an internal installation; they again allow the organization of arrays, but by means of the server itself.

Note that external devices with one slot can be powered from the USB port, but several drives in this case inevitably require a separate PSU (see "Power").

The maximum storage capacity supported by the pocket. In models with multiple disks/SSDs (see "Drive Slots"), this item indicates the largest total volume supported by the device; by dividing this capacity by the number of slots, you can determine the maximum allowable capacity of each individual drive.

The limitation on the maximum volume is relevant mainly for external models, including docking stations (see "Type"). This is due to the fact that fundamentally different interfaces are used for the drive and for connecting the pocket itself in such models (most often SATA and USB, respectively, see above for details). For the normal interaction of such interfaces, an electronic controller is required; and the larger the volume of the installed drive (s) — the higher the requirements for the performance of such a controller.

Note that, other things being equal, supporting large volumes is more expensive, and capacious drives themselves are not cheap. Therefore, when choosing according to this indicator, it is worth considering real needs, and not chasing the maximum numbers.