Quiet but audible 'zing' noise when disk rotated!


I have a couple of 2.5" HDDs bought from Amazon. The model is Hitachi HTS721010 A9E630 Travelstar 7 K1000 1GB. I fitted one in each of my laptops. I notice that when I rotate or twist my laptops there is a quiet but audible high pitched buzz or ‘zing’ from the disk. Its almost as if something is scraping or rubbing (imagine a circular saw but whisper quiet!). I want to know if this is normal? Could it be the gyroscopic effect of the disks inside the unit trying to twist as they are rotated? Maybe something is contacting something else? The read/write head contacting the disk? Or is it just the motor trying to maintain speed? Please let me know if this is NORMAL sound or NOT. If NOT I will return both disks. I don’t want to fill with data then find they fail later. The quicker I rotate the louder the noise, but as these disks are supposed to be for a laptop then they should cope with movement.


that happens to me too