External and internal hard drive for laptop

In recent years, it is becoming more importantthe problem of choosing a convenient storage device. Famous compact discs, first appeared in 1982, went through a long and glorious development path. Initially, this disk could store 700 MB of data (the first models with 650 MB quickly evolved). With the increase in the volume of software distributions, more capacious disks were needed - so the DVD appeared. Currently, the most popular technology is Blu-Ray with its 25 GB and more capacity. But more and more often the opinion is voiced that the development of CD-ROMs for backup and storage tasks will be completed, giving way to solid-state media. This is not always obvious, but the progress in this area is especially closely watched by laptop owners. Replace the CD-ROM drive or install an additional hard disk inside the system unit of the personal computer. But in laptops, everything is not so simple. The second hard disk can not be placed on a laptop by the usual way, because inside the case the components are very tight and there is no free space.

However, with the development of the USB bus appeared quitemany devices, including an external hard drive for a laptop. Unlike the usual varieties for internal installation, these hard disks (HDD) have a USB interface that supports hot-plug / unlock devices (which was not, for example, on the IDE). The hard disk for the laptop is connected very simply: just a USB cable coming from the HDD is included in any free corresponding port on the laptop. As a result, the operating system will determine the fact of connection and, if the disk already has a file system, automatically assign a letter, allowing you to work with the device. When selecting an external USB drive, it is recommended that you pay attention to the way the power is provided. Some models use a USB bus for communication with a laptop, but for power supply - a small external unit, which is less convenient. Others do not require such a unit, being content with 500 mA from the port (or 1 A, in case of using Y-Cable). Nevertheless, it is worth noting that models with a power supply often have higher speed and capacity. External HDD is most often used as a backup storage of important data or a portable device (remembering CDs).

Hard drive for laptop and computer (PC)are chosen in different ways. If for PC the main criterion is productivity and capacity, then for portable models energy efficiency is added to the list. After all, a mobile computer should run on battery for a long time, which is why a hard disk for a laptop almost never comes with 10,000 spindle revolutions. Such a solution would be very wasteful in terms of battery power consumption.

Buying an internal hard drive for a laptopIt is necessary to determine the type of interface. At the moment there are two: IDE and SATA. They are not compatible with each other, so the HDD interface and the controller on the motherboard must match.

The spindle rotation speed (RPM) determinesperformance, heating and energy consumption. The fastest models are from 7200 revolutions, the compromise version is 5400, and the slowest ones (are encountered less often) are 4200. The higher the rotation speed, the more heating and energy costs.

One of the characteristics of the hard drive is the amount of cache. The more it is, the better.

Currently, there are hard drives based onsolid state flash memory. They do not have moving mechanical parts, have low energy consumption, weigh little, and speed characteristics approach (and even outrun) analogs with magnetic disks inside. One of the disadvantages is the high cost.