What is mSATA? A Look at the Smallest New Hard Drive Interface

The SATA Problem

Before we talk about what mSATA is, let's talk about why SATA is becoming a problem.

SATA is a method of connecting a hard drive to a computer. It's an acronym for Serial Advanced Technology Attachment, although that underlying meaning is so rarely referenced today that it's arguably no longer relevant. This connectivity option was developed as an industry-wide standard capable of handling the high bandwidth potential of new hard drives. Another important advancement was a reduction in size. The common previous solution, called PATA, used a massive ribbon cable.

The modern SATA connection seemed quite tiny at the time it was developed, it has had a good run. However, as small laptops and tablet computers become more prevelant, companies are looking to introduce hard drives even smaller than the current 1.8" and 2.5" models found in many devices.

Many companies, such as Apple, have decided to get around the size restrictions of SATA and SATA compatible drives by soldering memory chips directly on their device's hardware. This saves space, but it also reduces future upgrade options and increases the cost of repairs. This leaves companies with a problem of compromise where neither option is ideal – they can use their own solution to connect long-term memory to the device, thus decreasing compatability and increasing repair costs, or they can use SATA and make concessions in their design.

Introducing the Solution


But there is a third way, and it's the same solution that led to the development of SATA over a decade ago – a new industry standard, capable of accommodating extremely small designs but also making upgrades and repairs easier.

That new standard is called mSATA. No, they're not much for originality. I would have called it the MAVERIC (minature angry velociraptor eagerly residing in computers) but I have no say over such things.

So mSATA is just like SATA but smaller, right? Yeah, basically, that's true. The size of the connectors on an mSATA drive are about half the size of those on a normal SATA hard drive. But this doesn't mean a drive will only be half the size – in fact, most of the new mSATA drives are about a quarter of the size of their average-size counterparts.

For example, the new Intel 310 drive is about 2 inches long and 1.2 inches wide (and about .2 inches thick). The smallest traditional drive from Intel, the 1.8 inch format 320, is 3.2 inches long and 2 inches wide. The more typical 2.5 inch format drive is nearly 4 inches long and 2.7 inches wide.

Practical Considerations

What is mSATA?

As you might expect, the new smaller format isn't compatible with your standard SATA connector. In an odd twist, the mSATA connection is "mechanically compatible" with mini PCI Express. This means that an mSATA drive that is lacking any sort of casing will fit into a mini PCI Express slot. However, the "mechanically compatible" phrase is important – it means the drive will fit, but won't necessarily work. Be very careful to read up on what your motherboard or device does and does not support.

What about speed? Well, mSATA can support the SATA 3/Gbps standard, but not 6 Gbps (yet). Although this is a limitation, it is a small one. The number of hard drives that can saturate a SATA 3 Gbps remains vanishingly small, and will probably remain small for a couple more years at least.

So far, consumer-level support for mSATA is extremely limited. The only drive commonly available that uses mSATA is Intel's 310, and it's usually sold out. There also aren't many consumer laptops or motherboards that are compatible with the new standard. If you're interested in using mSATA, you'll need to pay very close attention to the specifications of any hardware you purchase.


The fact that mSATA exists doesn't mean it will become the standard in the future. I think it is a logical next step for smaller devices, but it is possible that manufacturers will want to solder memory onto their products more frequently.

The fact is that it's only now, with the introduction of cost-effective solid state memory, that manufacturers have even enjoyed the option to put memory on their devices. While it increases repair cost and restricts future upgrades, it also (usually) reduces initial costs. Those less trusting – like myself – also notice that it increases the chance that a consumer will have to buy a new product if the long-term storage fails.

Still, laptops and some desktops are likely to make substanial use of mSATA, at the very least. This will be just one more connection joining a confusing pantheon that includes Thunderbolt, Firewire, USB, SATA, PCI and more.