The amount of internal hard drive memory. This memory is an intermediate link between the high-speed computer RAM and the relatively slow mechanics responsible for reading and writing information on disk platters. In particular, the buffer is used to store the most frequently requested data from the disk — thus, the access time to them is reduced.
Technically, the size of the buffer affects the speed of the hard drive — the larger the buffer, the faster the drive. However, this influence is rather insignificant, and at the level of human perception, a significant difference in performance is noticeable only when the buffer size of the two drives differs many times — for example,
8 MB and
64 MB.
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.
Main material used for external hard drive enclosure (see "Performance").
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Plastic. The most common option. Plastic is light, cheap, quite practical, including has good strength properties. In addition, it allows you to create cases of complex shape and almost any colour.
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Metal. Usually, aluminium-based alloys are used for metal cases, but other options are also found. Anyway, such cases are much stronger than plastic ones, and also have a stylish appearance. On the other hand, in terms of impact protection, this material has no advantages over plastic, but it costs much more, and it can weigh much more (depending on the specific alloy).
—
Rubberized. In this case, it usually means an additional external coating of rubber applied to a plastic or metal case. All rubberized cases are classified as shock resistant (see Features/Features) — thanks to their softness and resiliency, this coating provides additional protection against impacts. In addition, this material does not slip in the hands, thereby reducing the risk of dropping the device.
— Leather. Housing made of hard material (metal or plastic, see above) covered with natural or artificial leather. Such a coating plays an exclusively aesthetic role: it gives the hard drive a solid appearance, actually turning the device into a fashion accessory. At the same time, the use of
...leather significantly affects the cost; so paying attention to such models is for those for whom the design of the drive is no less important than the functionality.
