Advantages and Disadvantages of External hard disk drives
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They are being offered with ever increasing capacity and at ever decreasing prices. Many are advertised using ‘pence per Gigabyte’ prices as a lure. However a few notes of caution arise from the recent spate of external hard drives being sent for Data Recovery.
Unlike the internal hard drive in your PC, which is held securely in a rarely moved case, external drives are being carried about from place to place and as a result they get dropped, knocked, crushed and subject to all manner of abuse and trauma.
They have trailing power and/or data cables that only too easily serve to pull them over, drag them off desks or otherwise expose them to further risk.
Unlike the hard drive in your PC or Laptop, which is cooled by a fan, external drives seldom have cooling fans and, in an effort to make them as small as possible, the hard drive(s) inside rarely have much free air space around them. This can result in overheating with the attendant problems that causes.
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The hard drives found inside externals are no less likely to fail than an internal drive. Indeed where the drives inside an external are invisible to the user and perhaps chosen to keep costs low, might they be more likely to fail even without the extra risks highlighted above? Where external drives carry extended warranties, this might seem reassuring, but remember, the warranty will only cover repair or replacement of the drive, not the cost of recovering any valuable data stored on it.