When I push the button to start my PC, I hear a sound from the PC. Sounds like the cooling fan is hitting something. I then open the casing and checked but all the cooling fans are not touching anything. I also realise the sound seems to be coming from the hard disk. Then, the booting system said "PRIMARY HARD DISK FAILURE". What does this mean and will I be able to recover my data or to save my hard disk?? Please help!!!