Please ask questions about hard disk parameters and common hard disk parameters

A hard disk is made up of multiple storage disk sets, and the capacity of a single disk is the maximum amount of data that can be stored on a single storage disk. The following are the common hard disk parameters that I have collected and sorted out, welcome to read.

Rotational speed

Refers to the speed of the spindle motor of the hard disk per minute (driving the disk), for example, 5400 rpm means that the spindle speed in the hard disk is 5400 revolutions per minute. At present, the speed of desktop hard disk is still 7200 rpm, while the speed of mainstream notebooks is transitioning from 5400 rpm to 7200 rpm, and the performance has been significantly improved.

Single-disc capacity

One of the quite important parameters of a hard drive. A hard disk is a combination of multiple storage disks, and the capacity of a single disk refers to the maximum amount of data that can be stored in a single storage disk. At present, with the help of vertical recording technology, the capacity of a single disc has grown to 667GB.

It can not only increase the total capacity, but also help reduce the production rate and improve the stability of work. And the larger the capacity of a single disk, the faster its internal data transfer rate.

Average seek time

It refers to the time taken by the hard disk to move the read/write head on the disk to find the corresponding target data on the specified track, in milliseconds. When the capacity of a single disc increases, the head's. Seek action and distance traveled are reduced, resulting in a reduction in mean seek time and faster hard drive access.

Caching

A temporary place where hard drives exchange data with the outside. When the hard disk reads and writes data, the cache acts like a transit warehouse, constantly writing data, emptying and writing data again. Most hard drives currently have a cache of 32MB, while for large capacity products, it is 64MB.

Internal data transfer rate

Refers to the data transfer rate between the hard disk head and the cache, which is simply the speed at which the hard disk reads data from the platter and then stores it on the cache. The internal transfer rate can clearly indicate the read and write speed of the hard disk, and its level is the decisive factor in evaluating the overall performance of a hard disk. At present, most of the desktop hard disks are basically between 70-90MBS, and the notebook hard disks are around 55MBS.

As the data memory of the computer system, the capacity is the most important parameter of the hard disk. The capacity of a hard drive is measured in megabytes (MB) or gigabytes (GB), 1GB = 1024MB, 1TB = 1024GB. However, hard drive manufacturers usually take 1g = 1000MB when nominal hard disk capacity, so the capacity we see in the BIOS or when formatting the hard drive will be smaller than the manufacturer's nominal value.

The capacity of a hard drive also includes a single disk capacity. The so-called single-disc capacity refers to the capacity of a single-disc platter, and the larger the single-disc capacity, the lower the unit cost and the shorter the average access time. For users, the capacity of a hard drive, like memory, is always too little, not too much.

At present, the capacity of hard disks is generally 1TB for a single disk, that is, the hard disk that buys 4TB is generally 4 disks. At present, there are three directions for the development of mechanical hard disks: increasing the size, increasing the disc, and increasing the density of the disc.

The size is impossible, the inch has been eliminated. Disc density is not easy to increase without new technology. If you increase the number of discs, you will be limited by the thickness, so you should reduce the thickness of a single disc.

HDD has reached a bottleneck. Rotationl speed or spindle speed is the rotation speed of the motor spindle in the hard disk, that is, the maximum number of revolutions that the hard disk platter can complete in one minute. The speed is one of the important parameters to indicate the grade of the hard disk, and it is one of the key factors that determine the internal transmission rate of the hard disk, which directly affects the speed of the hard disk to a large extent.