There are some tell-tale signs that your hard drive may be failing and you could therefore end up losing your data.
Boot Failure: Sometimes, it is possible for one to switch on the computer and it refuses to boot. This may occur as a result of the hard disk containing bad sectors in some disks and/or even corrupted boot record data. Most of the time, booting is done from the hard disk and if there is a problem with the hard disk, then it would be difficult to have a proper boot.
Unusual Sounds: In some cases, when the computer is running, one can be able to note some unusual click sounds (whirring or buzzing), that can either be at regular or irregular intervals. It is advised that once this has happened to contact a computer specialist. This sound may come as a result of a broken actuator arm or failure of a servo motor. The best thing to do is to backup your data immediately and contact a data recovery specialist in case some data may go missing.
Appearance of "Blue Screen of Death": When a computer is running, and a blue screen with a lot of information written on it appears and usually reboots automatically. This is what we refer to as the "blue screen of death". It is usually a crash recovery program that tries to recover data that has been lost. One of the principle causes of its appearance is hard drive failure. Therefore, the next time it appears, check on your hard disk.
No sound of read/writing: Whenever data is read/stored from a storage device, there is usually some sound from the hard drive that signals reading or writing. If there is no sound then that may be a signal that there is a problem with the hard disk drive. Such a phenomenon may be caused by excessive heat emitted by the CPU that causes some components within the hard drive to expand and touch other components within the hard drive.