Whenever i play League of Legends i have 100-130 FPS in game and sometimes in drops fps between 10-30seconds in every game.
I'm planning to buy a new hard disk.
Well do you have a hard drive or ssd? Also, what graphics card do you have? How old is your gpu? While it is possible for the hard drive to be the reason for frame drops, there can be other reasons.
Why is your HDD health at 83% is the real question.
Please host a screenshot of your CyrstaDiskInfo SMART output on an image sharing site and link us to it so we can have a peek at what is going on.