HDD suddenley wakep UP!

Few months back my second HDd (40GB) GAVE A SOUND WHILE I'M IN THE WINDOWS AND AFTER FEW DAYS IT CRASHED GIVING ME SOME CHANCE TO RECOVER DATA BEFORE SAYING GOODBYE. So i left it aside thinking it might be useul to me in someday. After one or 2 months later i accidentley plugged it back to my machine and it works!!! Can somebody explain how can this happen? So far i created a one big partion and keep on cheking copying some files into it and to make sure it is ok. Only diffrence it thius time i'm having a new mobo after my last one died without reason.

It's entirely possible that the physical removal and re-installation of the drive either jarred loose a jammed mechanical component, removed a shorted electrical circuit or re-attached an open electrical circuit. There's a good posibility that one of the circuits in question may have been either the connectors or the IDE cable.