then your HDD is dying..
Clicking noise is bad head placement, and try hdd it self try to normalize position, but it can't.
Most of clicking situation, will scratch platter, and make a lot bad sector..
I suggest you to back up your data as soon as soon as possible, and if your drive still under warranty, then claim it..
my question is..what is your psu..?
Many problem like this is because of bad psu..