Helium
Hard drives in which sealed cases are filled with helium from the inside.
The meaning of this hardware is twofold. First, the density of helium is seven times less than the density of air. As a result, such a filler creates less resistance during the rotation of the plates, which has a positive effect on both energy efficiency and heat dissipation, as well as on the speed of data access. Secondly, helium is an inert gas, which means that it does not chemically interact with the internal parts of the drive, and the likelihood of corrosion (and so, in principle, low) is reduced to an absolute minimum. On the other hand, the production of
helium HDDs is a very expensive process. Therefore, most of these drives are either professional server solutions or advanced drives for home PCs of the appropriate level.
Cache memory
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.
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).
Shockproof
A parameter that determines the resistance of the hard drive to drops and shocks during operation (that is, in the on state). Shock resistance is measured in G — units of overload, 1 G corresponds to the usual force of gravity. The higher the G number, the more resistant the disc is to various kinds of concussions and the less likely it is to be damaged, say, in the event of a fall. This setting is especially important for external drives and drives used in laptops.
MTBF
Guaranteed (minimum) hard drive uptime. The longer the time between failures, the more durable and reliable the device. At the same time, we note that after this time, the drive will not necessarily fail immediately — most models remain operational even after the claimed resource has been exhausted, but the manufacturer does not give any guarantees here.
