Why Does a Hard Drive Go Bad?

While purchasing a new hard drive, perhaps you never thought that it may crash. Yet a hard drive is primarily a mechanical device, bound to fail at one time or other. You will be surprised to know that 44 percent of all data loss occurs owing to hard drive failure. Every hard drive has a definite life span, ranging from 3 to 6 years. Hard drive manufacturers indicate the possible life span of a hard drive, by giving a Mean Time Between Failure figure on the packaging and promotional literature. It is calculated by running a hard drive under laboratory conditions for some time and then estimating the resultant wear and tear, so as to extrapolate the average life span of a hard drive. However, MTBF is not an accurate indicator of the life span of a hard drive. There are many unconsidered external factors, which may cause a hard drive to crash. It is impossible to understand the vulnerability of a hard drive to these factors, without first having an idea about the internal configuration of a hard drive.

Internal Configuration of a Hard Drive

A hard drive consists of several hard, round platters, coated on both the sides by some magnetic material, so as to store data in binary notation, consisting of 0s and 1s. The platters are fitted on a spindle, which rotates at a very high speed, from 5,000 to 10,000 rpm. Positioned over these platters are the read/write devices, known as heads. Read/write heads hover over these platters, at a microscopic distance from them. The heads perform various important functions like reading and writing the data on the platters, communicating with the rest of the computer, etc. The platters are coated with a non-electrostatic lubricant and can hold large volumes of data. Besides the given parts, a hard drive has some electronic components also.

Causes of Hard Drive Failure

1) Mechanical Failure

Mechanical failures may occur due to mishandling or vibrations. The most common type of mechanical failure is ‘head crash’. In a head crash, the read/write head may land over the data storing magnetic surface and may seriously damage it. Common symptoms of a mechanical failure are the ticking or clicking noise made by a hard drive, when it is switched on. A head crash is a serious situation and may lead to a permanent loss of data. Any attempt to retrieve data on your own, by dissembling the hard drive or by using the DIY recovery software, after a head crash may prove to be risky and counter-productive. Help should be solicited from data recovery professionals, who have the requisite expertise and infrastructure to recover data from a crashed hard drive.

A mechanical failure may also occur due to a faulty air filter. All the hard drives are fitted with an air filter, which equalizes the atmospheric pressure and humidity, within and outside a hard drive. Sometimes an air filter may go wrong and some untrapped dust particle may land on the data storing magnetic surface, causing a head crash.

2) Electronic Failure

Every hard drive has an electronic controller board. An electronic failure is caused due to some damage to this electronic controller board, owing to exposure to high temperatures, power surge or some other reason. The possible symptoms of an electronic failure are the inability of the drive to spin or a failure on the part of the computer to recognize the hard drive. In case of an electronic failure, the data storing magnetic surface remains intact and a 100 percent data recovery is possible.

3) Logical Failure

Logical failure mostly happens due to a corruption of the file system. It may occur due to various reasons such as a virus attack, accidental deletion of important files and folders, electrostatic discharge, etc. If your hard drive has suffered a logical failure; chances are that your data may still be intact and recoverable. The lost data can be recovered by using DIY recovery software. However, in case of a greenhorn, this may prove to be risky and may further complicate the problems.

4) Firmware Corruption

A firmware is a software code located inside a hard drive. Firmware corruption may lead to the breakage of communication between a computer and its hard drive. In a situation involving a firmware corruption, the data is often fully recoverable.

People’s Reaction towards a Hard Drive Failure.

People often respond with a range of emotions towards a hard drive failure, which may vary from a feeling of abject helplessness to blatant physical violence towards their computers. The thing to be kept in the mind is that a hard drive is just a mechanical device, bound to fail at one time or other. The need is to take proper precautions against it in the form of a regular backup, investments in antivirus and recovery software and a proper handling of the computers.






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