Form factor
The form factor in which the hard drive is made.
This indicator determines primarily the size of the device. But its more specific meaning depends on the execution (see the relevant paragraph). So, in the case of external drives, only the overall dimensions of the case depend on the form factor, and then quite approximately. But internal HDDs are installed in slots with a well-defined size and location of holes for fasteners; these holes are made specifically for one form factor or another. For desktop PCs, the standard form factor is
3.5", for laptops —
2.5" ; at the same time, there has been a recent trend in desktops towards miniaturization and the transition to 2.5-inch drives. Theoretically, there is an even smaller form factor — 1.8", but in fact it is used mainly among ultra-compact external HDDs.
Manufacturer's warranty
Manufacturer's warranty provided for this model.
In fact, this is the minimum service life promised by the manufacturer, subject to the rules of operation. Most often, the actual service life of the device is much longer than the guaranteed one.
Interface
— SATA. Nowadays, it is the most popular interface for connecting internal hard drives.
the first version of SATA provides data transfer rates of about 1.2 Gbps,
SATA 2 has a practical data transfer rate of about 2.4 Gbps (300 MB / s), and the most advanced generation of
SATA 3 has a speed of 4.8 Gbps (600 Mbps)
eSATA. Modification of the SATA interface, designed to connect external hard drives; not compatible with internal SATA. The practical data transfer rate is similar to SATA 2 at about 2.4 Gbps (300 Mbps).
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USB 2.0. The earliest of the USB standards found in modern hard drives — and exclusively external (see "Performance"). Provides connection to a traditional full-size USB port, provides data transfer rates up to 480 Mbps, as well as a rather low power supply, which is why drives with this type of connection often require additional power. In light of all this, and the advent of the more advanced USB 3.2 standard (see below), USB 2.0 is considered obsolete today and is extremely rare, mainly in inexpensive and early models of drives. However, a drive with this interface can also be connected to a newer USB port — the main thing is that the connectors match.
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USB 3.2 gen1(previously USB 3.1 gen1 and USB 3.0). The standard for connecting external HDDs, which replaced the
...USB 2.0 described above. Uses a traditional full-size USB connector, delivers data transfer speeds up to 4.8 Gbps (600 Mbps) and higher power ratings, making these drives easier to handle without external power. However, for the same reason, you need to be careful when connecting USB 3.2 gen1 drives to older USB 2.0 connectors — such a connector may not have enough power to power a newer drive.
— USB 3.2 gen2. Further development of the USB 3.2 standard (formerly known as USB 3.1 gen2 and USB 3.1). The maximum data transfer rate in this version has been increased to 10 Gbps, and the power supply can reach 100 W (supporting USB Power Delivery technology). At the same time, drives with this type of connection can also work with earlier versions of full-size USB connectors — the main thing is that there is enough power.
— USB-C 3.2 gen1(formerly USB-C 3.1 gen1 and USB-C 3.0). USB Type-C connection compliant with USB 3.2 gen1 capabilities. These features are described in more detail above, the difference from the “regular” USB 3.2 gen1 in this case lies only in the type of connector: this is a relatively small (slightly larger than microUSB) socket, which also has a double-sided design. Due to its compact size, USB-C is found both in full-sized PCs and laptops, and in compact gadgets like smartphones and tablets; some drives with this connection are initially capable of "mobile" use.
— USB-C 3.2 gen2(formerly USB-C 3.1 gen2 and USB-C 3.1). Updating and improving the USB-C 3.2 gen1 described above — the same USB-C connector and increased data transfer rate to 10 Gbps (as in the "regular" USB 3.2 gen2).
— IEEE 1394. Also commonly known as "FireWire". A universal connector, similar in capabilities to USB 2.0 (see above), but used much less often, and nowadays is practically obsolete.
— Thunderbolt. High-speed interface for connecting external peripherals. It is used mainly in Apple computers and laptops, although it is also found in equipment from other manufacturers. Note that in modern HDDs there are mainly two versions of Thunderbolt, which differ not only in speed, but also in connector: Thunderbolt v2(up to 20 Gbps) uses a miniDisplayPort plug, and Thunderbolt v3(up to 40 Gbps) — USB type C plug (see above). Thus, in some hard drives, USB-C and Thunderbolt connections are implemented through a single hardware connector, which automatically detects which computer input the device is connected to.
— S.A.S. Modification of the SCSI interface, provides data transfer rates up to 6 Gbps (750 Mb / s). It is used mainly in servers, in desktop PCs and laptops it is practically not used.
— Fibre Channel. Professional high-speed interface primarily used in server drives ("Purpose"); similar in many ways to SAS. Allows "hot" replacement of drives; the actual data transfer rate over Fibre Channel, depending on the version, can reach 12.8 Gbps.RPM
For drives used in a PC (see "Intended use"),
5400 rpm(normal) and
7200 rpm(high) are considered standard speeds. There are also
more specific options, including models with the ability to adjust the speed depending on the load. In server HDDs, in turn, higher speeds can be used —
10,000 rpm and even
15,000 rpm.
Data transfer rate
The speed of data transfer between the disk and client devices is determined by the type of drive, spindle speed, memory buffer size and connection connectors. The last parameter is the most important, since it is impossible to exceed the bandwidth of a particular interface.
Plates
The number of platters provided in the design of the hard drive.
Physically, a hard disk consists of one or more platters, on which information is recorded. Several plates can be provided in order to achieve the desired volume without increasing the form factor. At the same time, it is also necessary to install an appropriate number of reading heads in such a drive, which complicates the design, reduces its reliability, and increases the cost. Therefore, manufacturers choose the number of plates based on a reasonable compromise between these points, and for selection, this parameter is more of a reference than practically significant.
Average search time
The time it takes for the hard disk mechanics to find random requested data to read. For each specific case, the search time is different, as it depends on the location of the data on the surface of the disk and the position of the read head, therefore, the average value is indicated in the characteristics of hard drives. The lower the average seek time, the faster the disk works, all other things being equal.
Operation power consumption
The amount of power consumed by the disk when reading and writing information. In fact, this is the peak power consumption, it is in these modes that the drive consumes the most energy.
HDD power consumption data is needed primarily to calculate the overall system power consumption and power supply requirements for the system. In addition, for laptops that are planned to be used often "in isolation from outlets", it is advisable to choose more economical drives.
Standby power consumption
The amount of power consumed by the disk "idle". In the on state, the disk platters rotate regardless of whether information is being written or read or not — maintaining this rotation takes the energy consumed while waiting.
The lower the power consumption while waiting, the more economical the disk is, the less energy it consumes. At the same time, we note that in fact this parameter is relevant mainly when choosing a drive for a laptop, when energy efficiency is crucial. For stationary PCs, “idle” power consumption does not play a special role, and when calculating the requirements for a power supply, it is necessary to take into account not this indicator, but the power consumption during operation (see above).
