I had determined that i had a burnt hard drive that made the clicking sound.
I read the internet a especially these forums. I found this topic
western-digital-pcb-swap-rule-t8951-20.html and decided to buy another hard drive with a similiar PCB. As it appears, the disk ain't working. There's still the clicking sound, but it's different. And the hard drive is even recognized by BIOS as WD2000 08.02D08(donor HD identified properly as WD2500JD-22HBC0), compared to the burnt PCB which was not recognized by BIOS.
After trying to swap the PCB with no luck, I came across the info of switching the ROM. Is this really necessary?
Sorry for the noobines.