Recently my small niece has been playing with my pc components. I am currently in the process of building my own rig and have all the piece of the new PC lying around. Yesterday, I saw my niece playing with a magnet over my hard disk. This piece has been salvaged from my old pc and has data on it. Will the magnet have any effect on the data on the disk?
Magnets and its effects on PC hard drives
A magnet has the capability of damaging a hard disk completely and making it un usable. However it is only possible to cause high damage if it has high magnetic fields that has a pull force of approximately 450 lbs and above. I am also certain that is not the magnet your niece was playing with as she would have injured herself. A pull force of 450 lbs with a finger clumped between the magnet and the hard disk the force would hit hard and causing loss of hand. From that you need not to worry about any damage on your hard disk by the magnet.
Magnets and its effects on PC hard drives
Unless the magnet is very small, and even if your hard disk is old enough, it is safe. But if the magnet is very strong, then there is a high chance of loosing the data on the hard disk or it may even damage it permanently because of magnetic field interference.
With the advancement in science and computers, the modern hard disks are not really affected by external magnetic field. But still it is better to take precautions and keep all the magnets away from your electronic devices.