Hard Drives & Electrical Failures

Though hard drives have become more reliable, electrical failures still happen.

A computer's hard drive consists of both electrical and mechanical parts. As with other computer parts, hard drive parts have become smaller, faster and more reliable, though electrical failures may still knock the unit out of commission.

Power

If you have a power outage, this will cause your computer's components to shut down, including the hard drive. If the AC power has excessive electrical noise, the noise may cause either temporary hard drive glitches or permanent damage.

Interface

Every hard drive has interface circuits that send data via a USB, PATA or SATA cable. If the interface fails, the drive will appear to work, but it will be unable to send or receive data to the computer.

Motor Control

The hard drive's motor has an electronic controller that manages the motor's start and stop as well as its operating behavior. A drive with a bad motor controller won't spin its disk. It may make repeated clicking noises as it keeps trying to start the motor.

Head Pre-Amplifier

Though the hard drive stores digital data, its magnetic read/write head processes analog signals. If the signal pre-amplifier stops working, the drive can't retrieve data from the disk.

References

• Adroit Data Recovery Centre: Common Hard Disk Failures
• Icube Development: Data Recovery for Desktop Hard Drives
• ABC Data Recovery: Head Faults
• ReclaiMe: Unusual Hard Drive Noises