hi, i have two 80gig hard drives in raid 0. the past couple of days i noticed that either both or one of them is making some noise. it sounds like its loading a bunch of data but its not. it doesnt vibrate extra or anything. its just a high pitch sound like its loading. constantly non stop. i dont know what hard drive it is. oh also ive noticed that the two 80s together mounted in the same area vibrate together, just natural vibration but in a pulsing way. it vibrates alot then it slows a bit then it vibrates and gets louder then slowing again. its enough to vibrate the desk. i never noticed it untill a month ago. but whats worrying me is the loading sound. its loading but just a little quieter and a higher pitch. is this normal cuz ive never heard this before and ive never had a drive go out on me yet. thanks for your help