i've tried out two hard drive witht the same effect: On random and frequntly occuring instances, my hd sound like it just powers off, then just as quickly powers back on again. It sounds like when you have a really loud fan and you turn the fan off then on again. These 'hiccups' are about a 1/2 a second each, so very short, and last night was the first time i got an error message of someting about a write error to the hd.
I'm thinking it the power supply. Can anyone confirm this? Has this happened to anyone before?