Hard Disk Noises Explained

Before Solid State Drives, we had something called a mechanical hard drive that used magnetic platters. Each platter had its own set of tiny read/write heads. The heads were shuttled rapidly back and forth across the surface of the platters by stepper motors. 

These motors would chatter amiably, making a sound vaguely like a rodent living in your computer. A rodent with a small hammer.

Today I was working on my computer and one of my drives started chattering like crazy. 

Oh Oh, I thought. What new malware is on my machine?

After a few minutes I was stumped. I stood up and walked over to the machine, a large tower system which sits about a few feet away from my keyboard. The noise wasn't coming from inside the box! It was coming from the other side of the wall... from the kitchen... where I was boiling some eggs... the shells of which were bouncing around the pot making a noise not dissimilar to hard disk head chatter (when filtered through a wall while the air conditioner was running).