disk usage is often at 100%

Hi guys :)

I also have the same problem, my disk usage is often at 100%, and the largest process is no more than 2mb.
I'm currently using Asus U24E laptop, i3-2330m with 4gb memory.
I bought this laptop years ago and start using windows 8 since December 2012, everything is normal until today I saw my laptop is pretty laggy,
and when I check the task manager, the disk usage is often 100%,
so I can hear the sound of my running HDD, also I can feel a little vibration on the laptop because of that

I've looked for some solutions on the internet but I still have the problem:
Change my SATA port to ahci --> not working
Restore my system using system restore --> not working
Disable antivirus, antimalware, etc --> not working

Wish I could find out how to solve it would be really help :)