That goes for eSATA (external SATA), not for internal. AFAIK, connecting drives without shutting down can be a risky proposition; if you need that ability, you can get an external open enclosure, like Thermaltake's Blacx or something similar. That connects via USB to the PC, but allows you to plug in a SATA drive as needed. EVEn in this case, mounting/unmounting the drive is recommended, to avoid HDD errors.