What is the SATA Standard? Storage and Optical Drive Interface Explained for Custom PCs

The SATA standard is an interface specification mainly used for connecting storage devices. When building a custom PC, the term appears in various contexts, such as when connecting data transfer or power supply cables, or in places like M.2 slots.

The data transfer speed can change significantly depending on the version of the SATA standard supported by each part, so attention is required.

This article also explains how to choose based on motherboard standards, part names, performance, and compatibility.

≫ Related article: How to Choose a Motherboard for a Custom PC [Performance / Features / Compatibility]

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What is the SATA Standard?

The SATA standard is an interface specification for connecting storage devices such as SSDs, HDDs, and optical drives. It defines data transfer speed and method, connection interface, physical shape and size, and functions.

It is widely used in various computers, including desktop PCs, laptops, and servers.

SATA stands for “Serial ATA,” and offers faster data transfer speeds than the older Parallel ATA (PATA). The cables are thinner and easier to handle, which also helps improve airflow.

PATA, also known as IDE or ATA, was first introduced in 1986 and was the main interface standard for about 20 years.

However, due to physical signal limitations, it was difficult to increase data transfer speeds. To overcome these limits, SATA was established in 2003.

SATA Standard Versions

This section explains the evolution of data transfer speeds and improvements for each version of the SATA standard, from the earliest to the latest.

First, here is a table summarizing each version:

Now, let’s explain each version. For the 3.x series, the explanation is summarized to keep it concise.

SATA 1.0 (SATA I)

SATA 1.0 (SATA I) was established in 2003 as the first Serial ATA standard, with a maximum data transfer speed of 1.5Gbps (about 150MB/s).

Compared to PATA, this standard offers faster data transfer and allows the use of thinner cables, improving airflow and making cable management easier.

The maximum data transfer speed of PATA, in its final version ATA-7 (Ultra ATA/133), is 133MB/s, so the SATA standard at about 150MB/s is a bit faster.

With future version upgrades, data transfer speeds will increase, so the SATA standard overcame the data transfer speed limitations caused by PATA’s physical signal constraints.

SATA also supports hot swap, allowing storage devices to be replaced without shutting down the computer.

This is mainly useful for servers, where stopping services is not an option and quick maintenance is needed.

Especially, it plays an important role in improving system availability (keeping the system running without stopping due to failures) and reliability, which is crucial for business continuity.

SATA 2.0 (SATA II)

SATA 2.0 (SATA II) was established in 2004 as the successor to SATA 1.0, doubling the data transfer speed from 1.5Gbps to 3.0Gbps (about 300MB/s).

Since SATA 1.0 was established in 2003, this was a quick upgrade within about a year. This was due to rapid technological progress and the need to quickly respond to market demands at the time.

• Increasing Data Capacity
  In the early 2000s, the spread of multimedia content and high-resolution data made faster storage essential.
• Manufacturer Requests
  Storage and PC manufacturers had strong demands for new features, requiring quick standardization.
• Competing Technologies
  Other interfaces (like SCSI and early SAS) offered high performance, so SATA needed to stay competitive.
• Expanding Market Share
  Offering new features early aimed to expand SATA’s market share and establish it as an industry standard.

For these reasons, SATA 2.0 was established in such a short time.

SATA 2.0 added a feature called NCQ (Native Command Queuing), which efficiently processes multiple data requests, especially improving random access performance.

This made data reading and writing smoother and improved multitasking efficiency.

Also, hot swap became more stable, multiple devices could be connected to one port, and improvements were made in power management and data protection, enhancing reliability and efficiency.

*Hot swap means removing parts while the PC is powered on and running.

With many important features implemented in SATA 2.0, it became the standard in most computers after that.

SATA 3.0 (SATA III)

SATA 3.0 (SATA III) was established in 2009 as the successor to SATA 2.0, doubling the data transfer speed from 3.0Gbps to 6.0Gbps (about 600MB/s).

From this point, SATA 3.0 became the base for further version upgrades with added features, and is now the mainstream version supported by current storage products.

Current SATA SSDs have data transfer speeds of about 550MB/s, so with SATA 3.0’s 6.0Gbps (about 600MB/s), SSD performance can be maximized.

Furthermore, from SATA 3.2 onwards, new interfaces like SATA Express and M.2 are also supported.

In this way, more features and supported interfaces have been added, making SATA a more convenient and versatile standard.

About SATA Standard Compatibility

SATA standards are compatible, so older SATA storage devices will work when connected to newer SATA ports.

For example, a SATA 1.0 storage device can be connected to a SATA 3.0 port.

However, in this case, the data transfer speed will be limited to the maximum speed of SATA 1.0.

The shape of the SATA connector has not changed, so as far as connecting and operating goes, it is fine even if the motherboard’s SATA port and the storage device support different versions.

However, the data transfer speed will match the lower version, so be careful about this.

How to Check the SATA Version

There are mainly two ways to check the SATA version for each product:

• Check the specifications on the official product page
• Check using a hardware information tool

Although it is important to pay attention to the version, most recent parts support SATA 3.x, so there is usually no need to check the motherboard and storage versions separately when choosing parts.

However, just in case, here is how to check the version.

Checking the Official Product Page

By checking the specifications on the official page of the motherboard or storage product, the SATA version can be found.

If multiple storage devices are to be installed, it is also good to check the number of SATA ports on the motherboard and the number of SATA connectors on the power supply unit.

Checking with a Hardware Information Tool

If you want to check the SATA version of already installed storage, use a hardware information tool.

For example, with Speccy, you can check the SATA version like this.

SATA Standard Connection Interfaces

This section explains the various connection interfaces of the SATA standard, according to their shapes and uses.

Standard SATA [Mainstream]

Standard SATA is the most common and widely used SATA interface for connecting motherboards and internal storage (SSD/HDD), as well as optical drives (CD/DVD/Blu-ray) in desktop and laptop computers.

There are connectors for data and for power supply. The data connector is a thin 7-pin connector, and the power connector is a wide 15-pin connector.

M.2 [Mainstream]

M.2 is a small expansion card slot that can be connected directly to the motherboard, and is especially widely used for installing NVMe SSDs.

It is also used for connecting Wi-Fi and Bluetooth expansion cards, making it very versatile.

M.2 slots support different interfaces such as SATA and PCIe (PCI Express), allowing various types of SSDs to be installed.

When used as SATA, it operates at the same speed as conventional 2.5-inch SATA SSDs, but in a more compact form.

On the other hand, when used as PCIe for NVMe SSDs, data transfer speeds are much faster than SATA, greatly improving read and write speeds.

≫ Related article: What is an M.2 Slot? NVMe SSD / Wi-Fi & Bluetooth Dedicated Slots [Custom PC]

eSATA

eSATA (External Serial ATA) is an interface for connecting external storage to computers established in 2004, and is an extension of the SATA standard for external connections.

The theoretical maximum transfer speed is 3.0Gbps (about 300MB/s), which was very fast for external storage at the time.

At that time, USB 2.0 was mainstream with a transfer speed of 480Mbps, so eSATA was more than six times faster.

This made high-speed data transfer possible for external storage, offering better performance than other external connection methods like USB.

It was especially beneficial for quickly transferring large amounts of data, such as in video editing or backups.

However, eSATA did not become very popular and is rarely used today.

This is likely because eSATA does not provide power, so external drives require a separate power supply.

In contrast, USB can transfer data and supply power with a single cable, making it more convenient.

Furthermore, new standards like USB 3.0 and Thunderbolt appeared, offering even faster speeds and greater convenience than eSATA.

Especially, USB 3.0 quickly became popular because it offered much faster data transfer while maintaining compatibility with USB 2.0.

USB 3.0 was established in 2008, and Power eSATA, which added power supply to eSATA, also appeared that year, but USB became popular faster and eSATA fell out of use.

As a result, eSATA is now mainly used only in specific environments, and is rarely seen in the general consumer market.

mSATA

mSATA is a small SATA interface designed for compact computers, especially for use in laptops and small devices.

It offers the same data transfer speed as regular SATA, and its physical shape is similar to a Mini PCI Express slot, making it suitable for small form factors.

This makes it ideal for use in space-limited environments.

mSATA drives use the same Serial ATA protocol as regular 2.5-inch SATA drives.

In the early days, they were used in laptops and some desktop PCs, but with the advent of the M.2 standard, mSATA gradually lost its presence in the market.

M.2 offers a smaller and higher-performance interface, and supports the NVMe protocol for even faster data transfer.

For this reason, M.2 is now more commonly used than mSATA.

SATA Express

SATA Express is an interface that combines the advantages of SATA and PCI Express, overcoming the speed limitations of traditional SATA connections and achieving transfer speeds up to 16Gbps.

This allows storage devices like SSDs to reach higher performance.

SATA Express ports on motherboards look similar to regular SATA ports but have extra pins to support PCI Express signals.

This allows for faster data transfer when compatible devices are connected.

However, like mSATA, SATA Express adoption was limited.

One reason is that other interfaces like M.2 and U.2 offered higher speeds and more flexibility.

Especially, M.2 was adopted in many laptops and desktop PCs for its compact form factor and fast PCIe connection.

Also, SATA Express required special cables and connectors, which hindered its spread.

Additionally, motherboard and storage device manufacturers did not release many products supporting SATA Express.

As a result, SATA Express was mainly used in some high-end products, and now M.2 and U.2 supporting NVMe are mainstream, so SATA Express is rarely used.

U.2

U.2 is a storage connection interface mainly designed for servers and high-performance workstations.

As one of the SATA standards, it is used especially in environments that require large capacity and high-speed data transfer.

By using PCIe, it enables faster data transfer than traditional SATA connections.

This makes it valuable in environments where quick processing of large amounts of data is needed.

U.2 has a different shape from regular SATA ports and uses a special cable, but it supports 2.5-inch SSDs, making it easy to install in existing server racks, so the introduction hurdle is low.

This allows high-performance storage devices to be easily connected.

On the other hand, in the general consumer market, other interfaces like M.2 are mainstream, so U.2 adoption is limited.

Micro SATA

Micro SATA is a type of SATA interface designed mainly for small devices, especially used in 1.8-inch SSDs and HDDs.

It is suitable for laptops and portable devices that require a compact design. Like regular SATA, it handles both data transfer and power supply, but the connector is smaller.

This allows effective use of internal space in devices.

However, Micro SATA has fewer pins and a different connector shape than regular SATA, so compatibility needs attention.

As for popularity, it was once used in small laptops and portable devices, but with the appearance of newer interfaces like M.2, which offer faster and more efficient data transfer, Micro SATA is now rarely used.

Also, as devices become smaller, storage shapes and connection methods are diversifying, so designs that do not depend on specific standards like Micro SATA are increasing.

Therefore, Micro SATA is now mainly used for specific purposes or in older devices.

Summary: SATA Standard is Used for Storage and Optical Drives

This article explained the basics, versions, and other connection interfaces of the SATA standard, which is mainly used for storage.

Here are the key points again:

Recently, NVMe SSDs are often installed in M.2 slots, and the demand for optical drives is decreasing, so the use of the SATA standard may be declining.

However, SATA is still mainstream, and if a storage setup uses devices other than NVMe SSDs, SATA will be used.

The most important thing to watch out for is data transfer speed, which differs by version.

However, since SATA 3.x has been around for many years, most recent parts use SATA 3.x, so there is little need to check if a part is SATA 3.x.

Still, knowing about the SATA standard, which remains mainstream, is important for building custom PCs, so take this opportunity to learn about it.

This article also explains how to choose based on motherboard standards, part names, performance, and compatibility.

≫ Related article: How to Choose a Motherboard for a Custom PC [Performance / Features / Compatibility]

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PC Parts Estimation & Compatibility Check Tool

Automatically checks each component you need when selecting parts for a custom-built PC—perfect for beginners.