When purchasing a PC, users almost always pay the main attention to the parameters of computing components. The choice of a hard disk is often based only on a measure of volume. This approach is absolutely wrong, because the HDD provides storage of all information and access to it. A negligent attitude towards choosing a "hard drive" will make work at the computer uncomfortable. In the worst case scenario, you will subsequently have to pay twice as much for the data recovery procedure. The article will tell you about what characteristics of hard drives you need to pay close attention to when choosing such devices.
General information
A hard drive is the main storage device in the bulk of modern PCs. It records not only user data, but also files of the OS, utilities, programs.
That is why choosing a HDD is a serious undertaking. After all, any computer device is easy to replace with a similar one. A failed hard drive will require not only the purchase of a new HDD, but also the reinstallation of the OS and programs.
First steps
Before you start studying the issue, you should decide what the PC in which the drive is installed will be used for. The main groups:
- A laptop for everyday tasks.
- Powerful gaming PC.
- Office computer.
- Multimedia center.
- Long-term file storage.
- A portable drive that will not be permanently connected.
Only having decided on the specific purpose of using a PC can we say what technical characteristics of the hard drive are paramount.
The size
Size (or form factor) determines the width of the device. It is measured in inches. Today, the form factor of almost all drives is 2.5 / 3.5 inches. Small ones are usually installed in laptops. Large - in full-sized PCs, but no one bothers to equip a computer with 2.5-inch HDDs, special adapters are even available for this.
There are smaller magnetic drives, for example, 1, 0.85, 1.8. They are primarily used in small mobile devices and you do not need to pay attention to them when choosing a HDD.
The size of the "hard drive" determines its weight, as well as what power supply the drive requires for its operation. That is why external HDDs almost always include 2.5-inch devices. After all, the main characteristics of external hard drives are the mass and low power supply, the device should work from a USB connector. If you install a 3.5-inch drive inside the mobile HDD, you will have to organize a separate power supply, which will need to be plugged into a power outlet for the device to function properly.
Capacity
Capacity - HDD parameter that determines how much information can be stored on it at one time. It can not be left aside, describing the characteristics of the hard drives of laptops or PCs. Photos, games, software, music, films - all this requires an impressive "weight", and from year to year their requests for capacity only grow. For example, modern games or high-resolution video files can take up more than 30 GB. The capacity of 2.5-inch drives today by average standards is from 150 GB to 2 TB. Devices of size 3.5 can store 3-5 TB of information on themselves.
1 GB on a larger HDD will cost less. Of course, this should not push the consumer to buy a device with a capacity of 1 TB, if half is enough for him. However, it must be understood that buying a hard drive that can store less than 500 GB is impractical today. The savings will come out small (200-500 rubles), but the price of one gigabyte will be impressive.
Geometry
Choosing a HDD, you should not focus only on its volume. The characteristics of external hard drives and internal include many important parameters. These include geometry. It is described by the number of plates and the recording density on them. Geometry affects both the capacity of the HDD and the speed with which it works.
Data recording in the "hard drives" is made on disks (plates) made of aluminum or glass. They are covered with a ferromagnetic film. Reading or writing is performed by the heads located on the brackets. A gap of a few nanometers always remains between the plate and the head. Each disk is divided into a large number of radial tracks, which are divided into sectors. In such a scheme, the radius of the plates affects the access time and data reading speed.
At the edge where the tracks are longer, the reading speed is higher, since in one revolution the head goes through a larger number of sectors. Therefore, the characteristics of 2.5-inch hard drives are always inferior to 3.5-inch samples. An HDD may contain more than one plate. The recording density is characterized by the above parameters. The value determines how much information is placed on each track.
The total capacity of the HDD is the sum of the capacities on each drive. The first 1 TB Winchester included five plates. However, technology is evolving. The Hitachi- developed hard drives, whose characteristics allow them to be used in servers, are equipped with ultra-modern plates. The capacity of each is approximately one gigabyte.
Today, the market for accessories offers drives with a very different number of magnetic disks and recording density. If you need the most efficient HDD, it is best to pay attention to devices with a small number of plates.
I must say that in stores it is unlikely that the buyer will be given information about the recording density. On the official websites of manufacturers of hard drives, this parameter is also not always covered. Nevertheless, during the selection it is recommended to learn more about these parameters of specific models.
Spindle speed
The speed of writing and reading depends, in addition to density, on the speed of rotation of the spindle. Aluminum discs are mounted on a spindle - internal axis. The spindle and plates rotate simultaneously as a single system. The more revolutions she makes per unit of time, the faster the necessary sector will be under her head.
For home PCs, hard drives with a speed of 5-10 thousand revolutions per minute are produced. The lower this value, the less heat is generated during drive operation. The same parameter also affects the necessary power supply for the normal functioning of the device. Basically, drives with a rotation speed of 5400 revolutions per minute are installed on home computers and laptops. The same HDDs are most preferable for equipping them with multimedia centers and other devices, for which the first place is not the speed of reading data, but a low level of heat and energy consumption.
A speed of 10,000 revolutions per minute or more is considered excessive. Such drives rarely integrate into household appliances primarily because they are very noisy. If you need very quick access to data, it is better to pay attention to the SSD.
Interface
A Sata hard drive can be connected to any motherboard of a modern PC or laptop , its characteristics do not affect this feature at all. If your machine is more than ten years old, it probably needs an IDE drive. To find such a device in the store is almost impossible, because their release has been discontinued.
SATA is represented by two standards with backward compatibility - SATA2 and SATA3. Exchange of information on the first interface presented at maximum speed is about 3 Gb / s. On the second - 6 Gb / s. In addition, SATA3 has advanced power management features.
The main characteristics of the hard drive working through SATA2, "behind the eyes" cover the needs of the average user. The speed of reading data from the surface of the plate hardly reaches the threshold value provided by the tire.
Cache
A buffer, or cache, is an intermediate storage device. It is necessary because the read speed is different from the write speed. Also, PC devices that request information from the HDD may not always be able to instantly access it or, after some time, will require it again. Such data will also remain in the cache of the hard disk for some time. This reduces the downtime of the computing elements, but reduces the load on the plate.
The HDD cache for desktops and laptops varies between 8-128 MB. "Winchesters" for laptops are mostly equipped with 8-16 MB memory. PCs are mainly equipped with drives with a 32-64 MB buffer.
"On paper" hard drive HDD, whose characteristics are better, should work faster than competitors. In practice, this is not always true. For example, the Winchester buffer is almost not used during the recording of large files. In addition, the software “wired” to the controller installed on the HDD affects the performance of the buffer. Therefore, chasing hard drives with a huge cache size is not necessary. It would be more correct to compare specific indicators of the speed of reading and writing data from certain samples of drives.
MTBF
Describing the characteristics of hard drives, one can not say about MTBF. This abbreviation is a designation of reliability indicator HDD. Its decoding is mean time beatween failures. In Russian, this parameter is called MTBF. It indicates how many hours the magnetic drive can continuously work until the first repair. This feature is extremely important for server hardware or storage installed in long-term file storage. Typically, HDDs created specifically for this purpose have an average MTBF of 900,000 or 1 million hours. For example, this feature of the Seagate Constellation Series hard drive is just roughly comparable to the numbers above.
Random access time
This parameter determines how long it takes the head to move to any part of the track. Measure the characteristic in thousandths of a second. Access time is one of the most important parameters of the HDD. Average performance directly depends on it.
Less time allows you to perform basic operations faster. The heads of server models of drives are positioned in 2-14 ms. This parameter of hard drives for home appliances is usually 7-14 ms.
Noise level
No modern electronic device can operate absolutely silently. Hard disks, in addition to electronic elements, include rotating plates, spindle, read heads. Having so many moving elements makes the HDD one of the noisiest PC devices. According to this indicator, the “Winchester” is only inferior to the cooling system fans.
Noise is measured in decibels. The slower the spindle rotates, the less extraneous sounds occur during operation of the device. A figure of 26 dB is considered quite low. It is impossible to find at the same time a very quiet and very productive device. You always have to compromise and choose the HDD according to the characteristic that is most important.
Energy consumption
The characteristics of hard drives directly affect the power consumption of the device. Most strictly, you need to study the energy level of those HDDs that will subsequently be installed in laptops. The higher this indicator, the less laptop can run on battery power.
In addition to the above, the energy consumed by the "hard drive" during recording or reading is converted into heat. That is why it is not necessary to equip PCs with energy-intensive drives, into which it will then be impossible to put additional cooling elements.
Of course, the values ​​of the described parameter are easy to find on the manufacturer’s Internet resources, but trusting them is not always worth it. It is best to search the web for information from independent testers.
SSHD
SSHD is not an ordinary hard drive. They harmoniously combine the advantages of magnetic drives and solid state. In this case, the latter are used as an additional buffer. Thus, the read or write speed increases, and the price per gigabyte remains almost at the same level.
Although SSHD technology is quite promising, the market for computer components offers a small number of such devices. Basically, their size is 2.5 inches, and using such drives in desktop PCs is not always advisable.
The most easy to find Toshiba hard drives, whose speed characteristics are much higher than that of classic HDDs. After all, the files used by the operating system are already in the non-volatile cache, which means that turning on the computer and loading the main programs is very fast.