PC Interfaces 101

Inside The Box: Connections Inside A PC System

Serial ATA (SATA)

Four SATA connectors on a motherboard

SATA is the serial bus for mass storage devices, mostly hard disks, and designed to replace the older parallel ATA interface. First generation Serial ATA is already in widespread use, with a maximum net data transfer rate of 150 MBps. The cable may be up to a maximum of 3.3 feet (1 m) in length. Point-to-point connections are typical for SATA, with one end of the SATA cable attaching to the PC's motherboard and the other directly to the hard drive. No additional devices can share that same cable, as is possible with Parallel ATA (where each cable supports one or two drives). The advantage here is that the older configuration of pairs of hard disks as master and slave drives is no longer necessary.

Recommended: Many SATA cables are delivered with protective end caps, to prevent damage to the delicate contacts

SATA power adapter in various formats

Power delivery for SATA hard disks

Cables come in various colors

Although SATA was designed primarily for use inside a PC's case, there are products that make external SATA connections available, too.

Power may be delivered to SATA drives in either of two ways

1. with a classical Molex power connector as in this picture...

...or with a special SATA power cable as shown in this picture.

Uwe Scheffel