you're using IDE or sata. Check if the cables behind it is
attached firmly. Make sure the wires does not have any
damage(torn,snapped, ect.).
For hard price(new ones)
40GB ~70
80GB ~75
120GB ~80
160GB ~85
180 ~95
If your hard disk makes some ticking sound, or you put it to your
ear and you hear that your harddisk is trying to spin but then
slowed down back, confirm harddisk is spoilt