From Mac Guides
Serial Advanced Technology Attachment, also known as SATA, is a connection interface used inside modern computers for I/O access to mass storage devices, such as hard disks, SSD Drives and optical drives (SuperDrives, etc). It has nearly superseded the PATA (aka ATA & IDE) format because it has a faster transfer rate and has more features. The SATA II (aka SATA 300) format is nearing the speed of SAS SCSI disks.
Features & Notes
- Provides a transfer rate of upto 300 MBps (SATA II) or 150 MBps (SATA I) - faster transfer speeds than PATA (33-133 MBps).
- Uses a new connector as to avoid confusion and include new pin configurations.
- ATA/IDE drives are not compatible inside computers with a SATA bus and vice versa.
- Allows for hot-swappable drives, which PATA does not allow.
- Native Command Queueing (NCQ) speeds up access to multiple parts of the disk.
- eSATA (External SATA) allows external drives to be mounted at upto 300 MBps - nearly the same speed as internal SATA 300 drives.
Serial ATA & Macs
Apple began to include this interface with the PowerMac G5 and then later with the iMac G5., it was included with the MacBook, MacBook Pro and Mac Mini when they first went Intel. eSATA PCI Express and ExpressCards are available from third party vendors, and allow hot swappable drives to be connected to Macs with these buses.