How does HDD break?

My HDD is three years old. It was working just fine, and suddenly, and stopped. The bios setting says there s no HDD detected. Then I unplugged the sata cable of the HDD, and then plug it back in and it works. Then after about half an hour, the computer stops working again, same problem. And I unplugged and plugged... show more My HDD is three years old. It was working just fine, and suddenly, and stopped. The bios setting says there s no HDD detected. Then I unplugged the sata cable of the HDD, and then plug it back in and it works. Then after about half an hour, the computer stops working again, same problem. And I unplugged and plugged it back in again.

Is this because of my HDD? Is my HDD dying? Or is it because of the SATA cable? Please!! I need a quick answer.
11 answers 11