Why does the hard disk drive fail? First we should set aside the colloquial and obvious wisdom that everything built by humankind falls apart and fails sooner or later. Typically when we ask the above question there are at least two distinct reasons why it came to mind. The number one most common reason is because wed like to know if theres anything we can do to prevent failure of our hard drive. And the answer to question number one is: not very much — beyond a few common-sense behaviors. The important thing to remember in this regard is that hard disk drives almost always fail without warning. Some fail after 15 days, some persist without failure for 15 years, but in both cases failure is usually sudden, precipitous and completely unexpected. The second reason for inquiring about hard disk drive failure probably stems from what could be called scientific curiousity. On this matter there are some informative points to be made in the interest of technical edification, and it is this second question the following information will address. There are not only two main reasons why people ask the question thats the topic of this webpage, but there are also two main categories of hard drive failure: physical and logical. Sometimes its both. When its both, diagnostic evaluation can become a bit tricky since the logical fault will generally not become apparent until remedy of the physical fault enables extraction of drives recorded information (which includes your data) and placement onto another drive thats mechanically stable. Physical Failure If the system BIOS does not detect the hard drive, then theres a good chance your issue is a physical one. Physical failures can be either mechanical or electronic. Its not uncommon for both types of failures to occur more or less simultaneously; disk drive complexity being what it is, a fault in one section commonly precipitates a related fault in another section. Mechanical failure usually results from a breakdown of the high-precision internal moving parts or a head crash. You may get some kind of warning that a mechanical failure has occurred, or is about to. If your hard drive makes clicking, clanking, beeping, scraping or grinding (or any other unusual) noises, shut it down immediately and call a data recovery firm. In laptops, these sounds can be very difficult to detect. Allowing a hard drive to continue operation under such conditions (whether you can hear the sound or not) very often leads to permanent, non-recoverable data loss. When a hard drive has failed mechanically, software based remedies can only expand media damage while the attempts are being undertaken; data recovery may only be safely recovered by a full-service data recovery operation using processes performed within a cleanroom. The other most common physical issue is an electronic failure. All hard drives have a circuit board (PCBA: printed circuit board assembly), and this component allows the drive, among many other things, to communicate with the computer system and vice-versa, control positioning of the R/W (read/write) heads, orchestrate the recording or writing of new data, read back previously stored data by interpreting signals received from the heads originating as detected magnetic flux-reversals and converting them to ones and zeroes, keep track of thousands of emerging defects in the media, maintain organization necessitated by user editing of stored data files, and a long list of other things too esoteric for the scope of this document. Electrical failures are common and can occur almost just as easily on a brand new drive as an old one. Ambient heat around the drive unit can become a mortal enemy from outside the computer, causing either or both the electronics and the mechanism to fail, so, always keep your computer system cool and well ventilated. For example, dont keep your CPU or external hard drive next to a window where the sun is going to beat down on it and heat it up, or do check to make sure all the fans are working. Logical Failure Logical faults have to do with the previously recorded information (written upon the drive data storage medium) becoming inaccessible, or in more severe cases, improperly organized. These more severe failures are typically described as file-system corruption. Causes for inaccessible data include accidental formatting of the drive, deletion of important registry keys or other critical files, and also viruses or other malware. Physical damage to the media resulting from contact with the flying R/W heads can destroy a critical recording of information that leads to a logical fault (see first paragraph above). When logical faults cause apparent drive failure, your drive may still be recognized by the BIOS, it may not boot, but may appear to be normal otherwise. Another form of logical failure can occur from expected fatigue of the recording medium over time. The drives media is used to store magnetic impressions, which the drive electronically converts to the ones and zeroes we call data. This means that the magnetic plating on the platter(s) which spin inside your drive, and upon which data is recorded, has become subject to corruption or physical damage through an aging process. Gradual, very slow, yet nonetheless physical deterioration of the magnetic medium takes place with all hard disk drives. In the vast majority of cases, this point is moot, because mechanical breakdown takes place first, on average in roughly three years.
Posted on: Sun, 06 Jul 2014 06:44:10 +0000