2009/8/4 mcclnx mcc <mcclnx at yahoo.com.tw>: [snip] > > my questions are: > > 1. is this disk really "degrade" or not? > > 2. how O.S. can predicate disk going to failure? > > 3. do I need replace this disk now? I understand that the drive electronics can check things such as the time it takes to read a sector, number of failures per read, retries before success etc.. This information gets processed and reported to the OS via SMART as some others have replied. But I really just want to say that within one day of getting SMART errors, my disk failed.