Basics

What Is SATA? SATA Drives, Cables, and Speeds Explained

Updated October 2, 2026 •6 min read

If you’ve ever shopped for a hard drive or SSD, you’ve seen the word SATA. It’s on spec sheets, cables, and motherboard labels. So what is SATA, exactly? It’s the standard connection that has linked most hard drives and many SSDs to computers for about two decades. Knowing whether you have a SATA drive helps when you upgrade, buy a replacement, or need to rescue files from a computer that won’t start.

What is SATA?

SATA (Serial ATA) is an interface standard: the cables, connectors, and communication rules a storage drive uses to talk to a computer’s motherboard. It arrived in the early 2000s to replace the older Parallel ATA (PATA, often called IDE) standard, with its wide ribbon cables.

A SATA drive is simply any drive that uses this interface. That includes:

Most internal hard drives (HDDs), in desktops, laptops, and NAS boxes
2.5” SATA SSDs, the common laptop-sized solid-state upgrade
M.2 SATA SSDs, the stick-shaped kind (more on that below)
Internal optical drives (DVD/Blu-ray)

SATA revisions and speeds

SATA has had three main speed revisions. Each is backward compatible, so a newer drive works on an older port (at the older port’s speed) and vice versa.

Revision	Link speed	Approx. usable throughput	Also called
SATA I (1.0)	1.5 Gb/s	~150 MB/s	SATA 1.5Gb/s
SATA II (2.0)	3 Gb/s	~300 MB/s	SATA 3Gb/s
SATA III (3.0)	6 Gb/s	~600 MB/s	SATA 6Gb/s, SATA/600

A hard drive can’t come close to saturating SATA III, so for HDDs the revision rarely matters. SATA SSDs, though, top out around 550 MB/s, right at the interface’s ceiling. That limit is the main reason NVMe exists.

SATA connectors and cables

An internal SATA drive has two connectors side by side:

7-pin data connector (the smaller one): connects to the motherboard’s SATA port with a thin, flat cable.
15-pin power connector (the wider one): connects to the power supply.

Both are L-shaped, so they only fit one way. Laptops usually skip the cables entirely and plug the drive into a combined connector.

2.5” vs 3.5” SATA drives

3.5” drives are desktop and NAS hard drives. They need 12 V power for their motors, so a USB adapter for one needs its own power supply.
2.5” drives are laptop hard drives and SATA SSDs. They run on 5 V and can usually be powered over a single USB port through an adapter.

Both use the same SATA data and power connectors.

SATA SSD vs NVMe (and where M.2 fits)

This is where most confusion lives, because M.2 is a shape, not a speed.

M.2 is a form factor: a small, stick-shaped card that plugs directly into the motherboard.
An M.2 drive can talk over SATA (same ~550 MB/s limit as a 2.5” SATA SSD) or over NVMe using PCIe lanes, which is several times faster.
The two look nearly identical. The edge-connector notches give a hint: M.2 SATA SSDs usually have two notches (B+M key), while NVMe drives usually have one (M key). “Usually” is the key word, so check the model’s spec sheet.
An M.2 slot may support SATA, NVMe, or both. Your laptop or motherboard manual will say which.

For a deeper comparison, see NVMe vs SSD. For SATA SSDs versus spinning SATA hard drives, see SSD vs HDD.

What about eSATA?

eSATA was an external version of SATA, with a sturdier connector for plugging external drives directly into a SATA controller. It was faster than USB 2.0 at the time, but USB 3.x and Thunderbolt made it largely obsolete. You’ll mostly see it on older computers and docks.

How to tell if you have a SATA drive

Windows (PowerShell): run the command below. The BusType column shows SATA, NVMe, USB, or RAID.

Get-PhysicalDisk | Select-Object FriendlyName, MediaType, BusType

Windows (CrystalDiskInfo): the Interface field shows “Serial ATA” for SATA drives and “NVM Express” for NVMe. Transfer Mode shows the current and supported SATA speed (for example, SATA/600). See our CrystalDiskInfo guide.
Mac: open System Information (hold Option and choose it from the Apple menu). Drives appear under SATA or NVMExpress in the sidebar. Recent Macs use built-in NVMe-style storage, not SATA.
Physically: a 2.5” or 3.5” drive with the two L-shaped connectors is SATA. For M.2 drives, check the label or model number.

Why SATA matters for data recovery

Here’s the practical upside of SATA: it’s a standard. A SATA drive from a dead laptop or desktop can usually be connected to another working computer, which is often the quickest way to rescue files when the computer itself has failed but the drive hasn’t.

Rescuing files with a USB-to-SATA adapter

An inexpensive USB-to-SATA adapter or enclosure lets you plug a bare SATA drive into any computer’s USB port. Choose one that includes a power supply if you might ever connect a 3.5” desktop drive. Our guide on how to get files off a dead laptop walks through removing the drive and copying files safely.

A few cautions:

This only helps if the drive itself is healthy. If the drive is clicking, beeping, or not spinning, don’t keep plugging it in. Each attempt can make things worse. See hard drive clicking: what to do.
Encrypted drives stay encrypted. A BitLocker-encrypted drive will ask for its password or recovery key on the other computer and can’t be read without it.
If Windows offers to format or initialize the drive, say no. That prompt means it can’t read the file system, not that the drive is empty.

When there’s no SATA connector at all

Not every drive has a SATA port you can reach:

Some portable external drives, including some WD and Toshiba models, have the USB connector built directly into the drive’s circuit board. There’s no SATA connector inside to plug into an adapter.
Some external drives encrypt data in the enclosure’s own electronics. Taking the drive out and connecting it by SATA then shows unreadable data.
Many modern laptops, including recent MacBooks, have storage soldered to the logic board, with no removable drive at all.

In those cases, opening the case and swapping cables won’t help, and can make a professional recovery harder. If an external drive isn’t being recognized, start with external hard drive not showing up.

The bottom line

SATA is the long-standing interface that connects most hard drives and many SSDs to a computer, using a 7-pin data connector and a 15-pin power connector, at speeds up to 6 Gb/s with SATA III. M.2 is a shape that can be either SATA or the much faster NVMe. Because SATA is a universal standard, a healthy SATA drive from a dead computer can often be read through a simple USB adapter, but that only works if the drive itself is healthy and actually has a SATA connector.

If the drive itself has failed, or it’s a native-USB or soldered drive you can’t simply plug in elsewhere, our hard drive recovery service can help. It’s one flat $1,200 price for single devices, with free prepaid shipping, and you pay nothing unless the recovery succeeds.