The M.2 form factor is just a few years old but it’s already started to change how we build PCs and laptops. This connector type has opened up the potential streamlined designed motherboards for everyone from general users do people who need hardcore, performance-optimized machines.
This also creates a bunch of new questions about how the M.2 form factor works. What size cards do you need and how do they line up with different sizes for slots?
As a general rule, you can fit smaller M.2 devices into larger M.2 slots by using optional mounting brackets on your motherboard. It’s technically possible to fit a larger M.2 drive into a smaller M.2 slot, but you’re often limited by the physical layout of your motherboard.
Here’s a quick rundown of everything you need to know about the M.2 form factor.
Welcome To The World Of M.2
Are you upgrading your gaming rig or maybe you’re just looking to replace a failing SSD drive? You probably have been seeing different M.2 drives around as options for storage as well as other devices. M.2 is a new form factor for card sizes and it shows up in everything from laptops to PCS.
What Are M.2 Slots?
M.2 slots recently showed up as a designation of a new form factor for devices inside of your PC or laptop. These were originally called Next Generation Form Factor (NGFF), but M.2 has taken over as the dominant lingo for talking about these exciting devices.
M.2 first took off by replacing SATA SSD connections for compact devices like laptops. However, the slim form factor and powerful performance has led M.2 to jump into the ring for everything from standard PCs to performance tuned gaming rigs.
M.2 can connect with everything from the latest SATA to USB C. This makes it an incredibly versatile connector that gives you countless configuration options. This connectability makes it an ideal option for increasingly specialized computers and devices.
One of the biggest questions people have about M.2 devices is how the slots are sized.
M.2 Slot Sizes Explained
It can be a little bit hard to understand the M.2 slots sizes. When you get deep into assembling your own PC, there are countless numerical codes and other industry jargon that makes things hard to decipher for first timers.
The good news is that M.2 slot sizes are actually really easy to read. There’s a straightforward system for M.2 slot sizes that can help you decipher the size of a M.2 device. Here’s how it works:
- The M.2 format uses a numerical code to designate its size. After the “M.2” you’ll see a string of 4 digits. These can be broken down into the first two digits and the last two digits.
- The first two digits represent the width of your M.2 device. Here’s more good news. M.2 is standardized to 22 millimeters in width. That means your code will always look like “22XX.”.
Just to be fair, there are M.2 devices with different widths, but these aren’t sold for commercial use. They’re reserved for specialized devices and shipped directly to manufacturers.
- The next two digits are the length in millimeters. These range from 30 at the smallest to 110 at the largest.
Here’s a breakdown of the five most common M.2 sizings and their numerical codes:
- M.2 2230: 30 millimeters long.
- M.2 2242: 42 millimeters long.
- M.2 2260: 60 millimeters long.
- M.2 2280: 22 80 millimeters long.
- M.2 22110 (Also Written as “2210”): 110 millimeters long.
Can M.2 22110 Fit Into 2280 Slots? (AKA Can Longer M.2 Drives Fit Shorter Slots?)
The direct answer to can you fit a 22110 into a 2280 slot is no. The 2280 motherboard slot will not be long enough to accommodate the full length of a M.2 22110 device.
Remember that “2280” means a length of 80mm – and a space on the motherboard designated as being just 80mm cannot physically fit a 110mm M.2 card.
However, all M.2 devices use the same connector which means that you might be able to fit a 22110 into a 2280 if you have enough free space on your motherboard:
Your M.2 22110 will definitely hang off the edge or maybe even bump into other components. However, if you’re able to support the full length of your M.2 device, you can fit larger M.2 cards into smaller M.2 slots.
One thing to remember if doing this, though, is that some motherboards “disallow” longer M.2 cards because of the risk of the M.2 drive dropping down and physically touching the circuits below it. This can cause a short circuit.
That is why motherboard manufactures provide you with M.2 standoff pads and/or screws. These ‘raise’ the M.2 drive up slightly (and are also used to secure the M.2 drive later):
If you don’t have these standoffs in a particular slot, you might not want to risk installing a longer M.2 drive there in-case it does cause a short circuit.
What About Fitting An M.2 2280 Into A 2210? (AKA Can Shorter M.2 Drives Fit Longer Slots)?
You can easily fit smaller M.2 devices into larger M.2 slots. This is something that often trips up people who are building their first PCs. The M.2 slots size doesn’t refer to the connector that the M.2 uses, but rather the length of the card itself. Larger slots can easily accommodate smaller sized cards.
As the image above shows, the top PCIE-4 M.2 slot of the Asus B550-M Plus motherboard supports the following M.2 drive sizes:
Whereas the bottom M.2 slot (which is PCIE-3) supports the following M.2 sizes:
Other Slot Size Combinations
The M.2 slot sizes are capable of receiving smaller cards. Sizing down is often the easiest, but depending on the layout of your motherboard and what other devices you’re using, you might even be able to size up if you have enough extra space.
Remember this general rule, you can always size down when it comes to M.2 cards. You might run into some problems like connectors not lining up, but it’s common to see motherboards that are capable of accepting a maximum size and then most sizes smaller than that.
There are even ways to do some DIY stabilization to make sure that your smaller cards fit into larger slots without the risk of them coming loose.
What To Do If Your M.2 Drive Is Too Long For Your Motherboard?
So, you bought an empty device that’s not the right size for your motherboard. What are your options?
Well, if you bought an M.2 device that’s too small for your motherboard, you’re in luck. Modern motherboards ship with risers (or “standoff screws”) designed to support various lengths of M.2 devices. All you need to do is pick the riser that corresponds to the size of your device and screw it into give you your M.2 card the support it needs.
When it comes to an M.2 drive being too long, you’ve got some challenges ahead of you. The physical length of your M.2 device can’t be changed. You also typically can’t remove other components from your motherboard to make room. This means we’re going to have to get creative and think outside of the box to support an M.2 drive that’s physically too long.
This fix all depends on the specific model of motherboard you’re working with:
- If your M.2 drive just hangs off the edge of your motherboard, you might be able to rig a DIY platform that gives it the support it needs to remain stable and fully connected. Remember that the goal here is to avoid short circuits at all costs – the M.2 drive should never touch the circuits on the motherboard.
- If there are just other drives or devices in the way of your M.2 drive, all you need to do is unplug them. As long as your motherboards’ connectors aren’t in the way, you can just deal with an awkward sizing situation until you can upgrade to the right motherboard.
- Alternatively, purchasing an M.2 riser could work well. Just be sure that you don’t purchase a budget riser that could throttle your M.2 performance. For example, if you have a 6000 MB/sec PCIE-4 drive, don’t purchase a cheap PCIE riser that will limit you to 1500 MB/sec speeds.
Can I Add An M.2 Card If My PC Doesn’t Have An M.2 Slot?
You can definitely buy adapters to support M.2 cards if your PC doesn’t have an M.2 slot on its motherboard. These adapters can switch SATA connections to support M.2 as well as switching between M.2 M, M.2 B, and M.2 B+M connector types. However, you should know that you might not get a performance gain if your computer isn’t designed to work with M.2 cards.
Older motherboards simply weren’t built with M.2 cards in mind. This means that the technology physically built into the motherboard won’t be able to use the optimized power of an M.2 card. You might be able to get an adapter and install an M.2 card, but you might still be stuck with old school performance because the rest of your motherboard simply can’t handle what the M.2 card is capable of.