Carnegie Mellon University recently conducted a study that found that HD failure rates are actually much higher than reported. If you are in the market for a new drive, I?d suggest giving this one a good read. The Carnegie Mellon study examined large production systems, including high-performance computing sites and Internet services sites running SCSI, FC and SATA drives. The data sheets for those drives listed MTTF between 1 million to 1.5 million hours, which the study said should mean annual failure rates "of at most 0.88%." However, the study showed typical annual replacement rates of between 2% and 4%, "and up to 13% observed on some systems." HardOCP