In 2002, Seagate released an HDD technology called SATA (an acronym for Serial Advanced Technology Attachment), which used serial transmission instead of slower parallel transmission. Whereas PATA drives speeds of 33/66/133 Mbps, SATA drives boasted speeds of 150/300/600 Mbps. This meant that the lowest SATA transmission speed of 150 Mbps was faster than the highest PATA speed of 133 Mbps.
The connector interfaces of the SATA drives were also different, but it was common at the time to see SATA drives with connectors for both SATA and PATA power cables for backward compatibility.
SATA data cables are much thinner than PATA cables, as they only contain seven wires connecting to seven pins. SATA devices use one cable per drive, unlike PATA devices, which connect two drives on one IDE/EIDE cable connected in a master/slave configuration.
The following image shows an older SATA drive with SATA data and power connectors to the right, and a legacy IDE Molex power cable (four pins) to the left:
SATA still continues to be standard today for drive technology for both desktops and laptops, and has had several revisions as listed here. Speeds listed are in MBps and not Mbps:
- SATA 1: 150 MBps
- SATA 2: 300 MBps
- SATA 3: 600 MBps
The following image shows two SATA laptop 2.5-inch drives. The one to the left is damaged, and has been opened for us to see the circular platter at the middle with the actuator arm at the top, slightly positioned over the platter. At the end of the actuator arm is a read/write head, which actually does the reading and the writing of data to the platter.
The drive to the right in the image is actually a hybrid drive, or an SSHD (an acronym for Solid-State Hybrid Drive). This is actually a mechanical drive like the one to the left, but also has flash memory in it to allow for faster access to the data on the platters:
