My hard drive is not detected..

Maybe the HDD just died.....
Something on the PCB blew up....
Change the power connector to another one from the same PSU, change the SATA cable and then change the port to which it is connected.... That's the max that can be done.
If none of those make it work, then you can be sure the HDD's gone....

Every check up has been done already.. but i can feel the hard disk vibrating when powered..

As alyoshks has said "Change the power connector to another one from the same PSU, change the SATA cable and then change the port to which it is connected.... That's the max that can be done."