SATA cable functions, types, and advantages

Serial Advanced Technology Attachment (Serial ATA) is a standard of cables and connectors that are used to connect storage devices such as hard disks to the computer motherboard. SATA cables are used to transfer data and power to the device.

There are 2 main SATA cables, data and power cables. The data cable connects to the motherboard to transfer data. The power cable connects to a computer power supply to power the storage device. SATA cables’ main benefits are they offer a high data rate, support hot plugging, and are easy to work with.

Functions of SATA cable

The primary function of the SATA cables and connector is to transfer data and power between the device and the motherboard. SATA data cable transfer data at high speed from a storage device while a power cable is used to power the storage device by connecting it to the power supply unit of the computer.

SATA cable and connector design

The cables are made of a flexible material that has a flat design and is slim. This makes them flexible and easy to use and route within the computer casing. They are approximately 1 meter (3 feet) long. Depending on the purpose of the data cable it can either be straight-through which is used to connect the device to the motherboard. The other type is a crossover cable design that is used when connecting 2 devices directly.

On the other hand, the connectors are narrow to enable them to fit on the device and they have a mechanism that secures the device in place after the connection. To avoid damaging the device and the cable the connector can only be fitted from one direction. So always check before forcing the cable to the connector. For power SATA cable is has 15 pins that used to power the device while the data cable has 7 pins for data transmission.

Types of SATA cables

The cables can be broadly categorized into 2 main, SATA data and power cables.

  1. SATA data cables: These are used to connect SATA hard drives to motherboard ports or to SATA controllers. They have a thin, 7-pin design.
  2. SATA power cables: These are used to connect SATA hard drives to power supply units and provide the driver with the power it needs to operate. They have a thicker, 15-pin connector. 
  3. SATA data and power cables: These are combination cables that have both data and power connectors in one. They are useful for connecting drives to motherboards or controllers that don’t have dedicated power connectors. The connector is split to have one side for data and the other for power.

Generations and standards of SATA cables

From this broad category of cables, SATA can further the classified into generation or standards that have been developed. Mostly they differ on the data rate that each cable can support. They include.

  1. SATA 1: they are old versions and currently they are not commonly used. They had a bandwidth throughput of 150MBs and a data rate of 1.5Gbits
  2. SATA 2: they replaced SATA 1 generation. They support a bandwidth throughput of 300MBs and a data rate of 3Gbits
  3. SATA 3: it is the 3rd generation. It supports a data rate of 6Gbits and a bandwidth throughput of 600MBs. They have higher data transfer speeds than SATA 2 cables and are fully backward compatible with SATA 2 devices.

Other SATA types of cables are

For more details on the SATA standards, you can read on Wikipedia

  1. External SATA (eSATA): it is used for external connections. It connects external drives to the PC.
  2. Micro SATA: they are used for internal connections and backplane applications.
  3. Low Profile SATA: they are ultra-thin cables mostly used to connect graphic cards.

Advantages of SATA cables and connectors

  1. High data transfer speeds: SATA cables are capable of transferring data at speeds of up to 6 Gbps (gigabits per second) for SATA 3 cables. This makes them much faster than older technologies, such as IDE and Parallel ATA.
  2. Ease and simple to use: SATA cables are easy to install and connect. They have a small, 7-pin design and are very thin, making them easy to route and connect to hard drives and computer motherboards. They are also plug-and-play which means the user doesn’t require to install any software to use them. The drivers are installed together with the operating system 
  3. Widely available: SATA cables are widely available and can be purchased from most computer hardware stores or online. They are also very affordable, making them a cost-effective choice for connecting storage devices.
  4. Compatibility: SATA cables are compatible with a wide range of devices, including hard drives, solid-state drives, Blu-ray drives, and DVD drives. They are also backward compatible from one generation of devices to another.
  5. SATA cables a power splitter: this allows the cable to draw power from both the device and the motherboard. This allows the device to draw additional power if needed and helps to prevent power issues that can occur with some devices.
  6. Hot-swappable: SATA cables are hot-swappable, which means that you can connect and disconnect them while the computer is turned on. This is useful if you need to replace a failed hard drive or add a new one without shutting down the computer. This is good for servers if you have implemented RAID storage.

Disadvantages of SATA cable

  1. Incompatibility with older devices: SATA cables are not compatible with older devices that use parallel ATA (PATA) or IDE connections. However, you may need to buy SATA to PATA or IDE converter to use those devices.
  2. Limited cable length: SATA cables have a maximum length of 1 meter (3 feet), so they may not be suitable for use in cases where the devices are located farther apart. If you need to use it for longer distances you can extend it.
  3. Not suitable for external devices: SATA cables are not suitable for use with external devices, as they are designed for internal use only. However, we have eSATA which is used for external devices.
  4. A limited number of devices per connection: The SATA standard allows for a maximum of two devices per cable, which can be limiting when you need to connect more devices.

What is a SATA controller?

A SATA controller is a hardware component that allows a computer to communicate with and control SATA devices such as hard drives and solid-state drives. The SATA controller is responsible for sending and receiving data to and from the storage device and converting it into a form that the computer can understand. SATA controllers can be built into the motherboard or added to the computer as an expansion card. There are also external SATA controllers, which allow a computer to connect to SATA devices through a USB or Firewire port.