Ticking noise from HDD

Often, my laptop's HDD makes a chirp/ticking sound. Tracked it down to this issue and this fix.

In short, the issue is that the HDD's firmware is set to save power by parking its head; but the OS is accessing the HDD quite frequently. As a result, the HDD aggressively parks its head, and then has to unpark it because the OS does a read/write. Turns out this parking/unparking could wear out the driver faster than if there was no power management.

Additionally, this happens even when the laptop is on AC... where there is no power saving advantage.

The fix linked above simply turns off the HDD's power management.