Performance Characteristics of Hard Disk Drives

A Hard Disk Drive, or also known as hard disk, hard drive and HDD, is one of the vital parts of a computer and any other device that requires some kind of data storage. They can be found either built into the device in question or they can be used as an external storage part. Invented in 1950s, hard disks have gone through a great deal of developments and improvements. Although it wasn't even imaginable a few decades ago, today we can speak of hard disks with thousands of terabytes of storage capacity will soon be available to the average user.

Just like all the other components of a computer, hard disk drives also have some certain performance characteristics which define how good they are. Here, let me briefly mention each characteristic so that you will have an idea when you do some research to buy a new hard disk.

The most important characteristic of a hard disk is the data transfer rate. This is the measured amount of data that the hard disk can transfer per second. I am sure you are quite familiar with numbers like 5400 rpm, 7200 rpm or 10000 rpm, they represent the number of rotations that the disk can perform in a minute. A 7200 rpm hard disk has a data transfer rate of about 70 mb per second. This includes both reading and writing from a local disk.

Seek time is another important characteristic of hard disks. Ranging from 3 ms(high performance servers) to 15 ms (mobile drives). This is the time required for the read/write head of the disk to go to the correct point to start the reading or writing process.

Power Consumption. The speed and capacity of a hard disk are the main factors that affect its power consumption rate. Slower hard disks consume less power compared to higher speed hard disks.

Audible Noise is something that manufacturers want to decrease to a minimum level. You might not hear the audible noise of the hard disk of your PC or laptop but definitely you should have noticed the noise of an external hard disk drive before.

Replacement of Hard Disk Drives

I didn't want to close this post without mentioning the replacement of hard disks in a few sentences. Occasionally, you will need to change your hard disk due to several reasons like need for more storage or unexpected crashes and burns occured on the hard disk. If you are not a technology guru, let the experts do the replacement for you since there is always the risk of losing data or corrupting the system in a manner. For Apple Mac users, there is a website about replacement hard disk for macbook, where you can find lots of information about hard disk drives and their replacement.

Up to now, I tried to discuss about the performance charcteristics of hard disk drives, below you can find a number of helpful links related to computer hardware and hard disk drives in general.

• Hard Disk Drive - Learn more about hard disk drives on Wikipedia.org
• HDD - What is a hard disk drive?
• http://www.pcguide.com/ref/hdd/index.htm
• How Hard Disks Work

I hope this article was useful to you. Please let me know if you have any questions or comments about this post or hard disk drives.