The M.2 NVMe and M.2 SATA ports are identical. But, the software compatibility isn’t the same. In most cases, the port will not be physically compatible as well. Because the interface is different, these drives interact differently with the system. The NVMe drives use the PCIe interface which offers much higher bandwidth than the SATA interface utilized by the SATA drives.
The availability and software support of the ports depend totally on the motherboard manufacturers. So, it is always a good idea to double-check the user manual of your motherboard or laptop before you make a purchase. It is possible that there is an NVMe port in your system but doesn’t support it in BIOS. Also, some M.2 SATA-only ports may have an M-key which may confuse some people that the port is NVMe but in reality, it won’t support NVMe.
If your system has an M.2 NVMe port (slot on the right side), you can use any M.2 SSD on it because they support SATA SSDs as well. But, this isn’t the case with the M.2 SATA-only ports. M.2 SATA ports generally have a B-Key (Slot on the left side) or B+M Key (Slot on both sides). You can’t fit an NVMe drive in these ports. So, there is no point in talking about software compatibility.
So, in simple words, you can’t use an M.2 NVMe SSD in an M.2 SATA port because they are physically and logically incompatible.
Let’s talk in full detail about this so that you have no confusion left.
The Experiment
My HP Pavillion 15 laptop supports only M.2 SATA SSD and has a dedicated port for it. I upgraded it to a 256GB Kingston A400 drive. Let’s see if the laptop recognizes an M.2 NVMe drive. This should clear everything up.
1. The NVMe Drive
I am using a WD Green SN350 SSD for this experiment.
2. Opening the Laptop
Just take the screws away and reveal the motherboard by removing the back panel.
3. Installing the NVMe in the SATA slot (Doesn’t fit)
Oops! It’s a B-key slot. I can’t install my NVMe SSD inside it. The already installed M.2 SATA SSD is the Kingston A400.
Port Variations
Generally, you will find the M.2 SATA port with a B-Key notch. However, in some laptops and motherboards, the M.2 SATA-only port may have an M-Key notch but they may not support the M.2 NVMe drive. In this case, your NVMe won’t get inside the port because of the physical incompatibility.
This variability creates confusion. In the case of my laptop, it was easy to identify the type of SSD supported just by looking at the port. But, if this port had an M-Key, I might have ended up buying an NVMe which will not be supported on the software level by the CPU.
Physical Compatibility
M.2 NVMe drive will always have a notch on the right side. The size will be the same as the M.2 SATA drive. But, it depends on the port whether you’ll be able to install your drive or not.
As we discussed earlier, the M.2 SATA ports can also look like an NVMe port. In this case, the NVMe can be physically compatible with your SATA port. But, that doesn’t always mean your system will recognize the drive.
Software Compatibility
The NVMe drives make use of parallelism and low latency in SSDs. For this to work, a PCIe interface is required. So, an M.2 NVMe port is generally allocated 4 lanes of the PCIe bus. Depending on the PCIe version, the total bandwidth is determined by the respective port.
The M.2 NVMe ports allow M.2 SATA SSDs because they also have the SATA lanes allocated for a wider range of flexibility.
The M.2 SATA ports don’t allow the M.2 NVMe drives because they need PCIe lanes to connect to the CPU. The M.2 SATA-only ports connect to the system by the SATA controller which is available on the motherboard chipset.
Types of M.2 SSDs
There are two main types of M.2 SSDs in the market. M.2 SATA and M.2 PCIe NVMe SSDs. However, there is an older type called M.2 PCIe that uses the AHCI protocol. M.2 SATA and M.2 NVMe SSDs are the most common ones. M.2 NVMe are the fastest ones and now the most popular.
The M.2 NVMe ports and cross-compatible with all three types of drives. If your system is a little older and has just the M.2 PCIe slot (non-NVMe), you won’t be able to get the most out of your NVMe drive. M.2 PCIe drives are rare these days. Again, the SATA port is just for SATA.
Things to keep in mind
The first and most important thing is to check your motherboard or laptop’s user manual. It will give you the details of the available ports and their compatibility. Sometimes, there are capacity limitations on the ports. If you are comfortable opening your laptop, you can look at the port physically. Most of the time, the supported type of SSDs are written over there. If not, you can just check the notch. If it is on the right side, it will surely accept both the SSDs. However, on the software level and in the BIOS, it is possible that the NVMe drive isn’t supported.
If you have purchased an NVMe and it isn’t working on your system, you can still use it as an external drive. But, it is wise to know your system’s capabilities before making a purchase.
I hope this helps.