The term SATA generally refers to the types of cables and connections that follow this standard. Serial ATA replaces Parallel ATA as the IDE standard of choice for connecting storage devices inside of a computer. SATA storage devices can transmit data to and from the rest of the computer much, much faster than an otherwise similar PATA device.
SATA vs PATA
Compared to Parallel ATA, Serial ATA also has the benefit of cheaper cable costs and the ability to hot-swap devices. To hot-swap means that the devices can be replaced without turning off the entire system. With PATA devices, you have to shut off the computer before replacing the hard drive. SATA cables themselves are much smaller than the fat PATA ribbon cables. This means that they’re easier to manage because they don’t take up as much space and can be tied up more easily if need be. The thinner design also results in better airflow inside the computer case. Like you read above, SATA transfer speeds are much higher than PATA. 133 MB/s is the fastest transfer speed possible with PATA devices, whereas SATA supports speeds of around 600 MB/s (as of revision 3.4).
Some Additional Differences
The maximum cable length of a PATA cable is just 18 inches (1.5 feet). SATA cables can be as long as 1 meter (3.3 feet), which provides some freedom to choose where devices can be mounted. However, while a PATA data cable can have two devices attached to it at once, a SATA cable allows just one. Some Windows operating systems don’t support SATA devices, like Windows 95 and 98. However, since those versions of Windows are so outdated, it shouldn’t be a concern these days. Another disadvantage of SATA hard drives is that they sometimes require a special device driver before the computer can begin reading data from it and writing data to it.
More About SATA Cables & Connectors
SATA cables are long, 7-pin cables. Both ends are flat and thin, with one often made at a 90-degree angle for better cable management. One end plugs into a port on the motherboard, usually labeled SATA, and the other (such as the angled end) into the back of a storage device like a SATA hard drive.
External Hard Drives
External hard drives can also be used with SATA connections, given, of course, that the hard drive itself has a SATA connection, too. This is called external SATA, or eSATA. The way it works is that the external drive attaches to the eSATA connection at the back of the computer next to the other openings for things like the monitor, network cable, and USB ports. Inside the computer, the same internal SATA connection is made with the motherboard just as if the hard drive were fixed inside the case. eSATA drives are hot-swappable in the same way as internal SATA drives. However, one caveat with external SATA hard drives is that the cable doesn’t transfer power, only data. This means that unlike some external USB drives, eSATA drives require a power adapter, like one that plugs into the wall.
SATA Converter Cables
There are various adapters you can purchase if you need to convert an older cable type to SATA or convert SATA to some other connection type. There are also Molex converters you can use if your power supply doesn’t provide the 15-pin cable connection that you need to power your internal SATA hard drive. Those cable adapters are pretty inexpensive, like this one from Micro SATA Cables.
How can you tell if a SATA cable is 6Gb/s? SATA 3 cables, or third-generation SATA cables, transfer data at six gigabits per second. One indication that your cable is a SATA 3 cable is a locking mechanism (latch) on one or both ends of the cable. If a latch is present, it’s a 6Gb/s SATA 3 cable. What is SATA Express used for? SATA Express is a bus interface that you can use to connect storage devices to a computer motherboard. Since it supports Serial ATA and PCI Express protocols simultaneously, SATA Express allows devices to choose the existing SATA method or use the faster PCI Express bus.