Hello everyone..!!.. In this blog, we’re going to talk about M.2 NVMe SSD Explained – M.2 vs SSD. So, let’s get started…
Now these drives are relatively new and have only been around for a few years now and just like regular 2.5-inch SSDs that we’re more familiar with M.2 SSDs also use flash memory for data storage and they are very fast.
But the difference between a regular 2.5 inch SSD and an M.2 SSD is that the M.2 is a
totally different form factor and it connects to a different type of slot.
The M.2 which was formerly known as the next generation form factor is a standard that’s used for mounting expansion cards internally.
Now SSDs have dramatically passed mechanical hard drives as far as speed and this is because SSDs have no moving parts.
Because they use flash memory for data storage as compared to mechanical hard drives that use rotating magnetic disks to store data.
But in recent years,
SSDs have gotten faster and are more capable of moving data at a faster rate.
So in order to unlock the full capability of SSDs engineers needed a new technology to unlock the faster speeds of SSDs and that’s where M.2 and NVM Express come in.
Now prior to M.2 and NVM Express the latest interface standard that was widely used for hard drives and SSDs was SATA 3.0 and the standard that was used for an interface for software to communicate with SATA was the advanced host controller interface which is better known as AHCI.
Now AHCI was developed primarily for mechanical hard drives. It wasn’t made or optimized for SSDs and that’s mainly because it dates back to 2004.
So it was creating a bottleneck for today’s SSDs.
The SATA 3.0 bus with AHCI allows data transfer speeds at a theoretical rate of 600 Megabytes per second, which is pretty fast.
However, M.2 NVM Express SSDs do not use the SATA bus.
They instead use the PCI Express bus, which is much faster than SATA.
So by using the PCI Express bus with an optimized protocol like NVM Express these allow SSDs to transfer data at a rate of 3 Gigabytes per second, which is extremely fast. So, M.2 SSDs with NVM Express is roughly 5 times faster than SATA and AHCI.
Now this speed will vary depending upon what motherboard you are using and which SSD.
But regardless it’s still a lot faster than SATA SSDs.
NVMe or Non-Volatile Memory Express is a communications protocol specifically developed for SSDs.
It basically reduces the CPU overhead and streamlines operations.
Which lowers latency and Increases input and output operations per second or in other words it’s fast.
NVM Express was developed to fully take advantage of the capability of PCI Express storage devices and to perform many of the input/output operations in parallel.
Meaning that many calculations are done at the same time.
A large job is broken down into several smaller jobs that can be processed independently.
Now this is very similar to how a multi-core CPU works with multiple threads where the CPU cores work independently of each other to perform certain tasks.
The command queue is a queue for enabling the delay of a command to be executed.
So in a nutshell as commands are sent to a storage drive it gets into a line or queue.
Then as each command is finished executing by the drive it goes to the next command in the queue.
Now AHCI allows one queue with up to 32 commands in the queue.
But NVM Express allows 64,000 queues and with each queue capable of 64,000 commands.
So in theory if you were to max out NVM Express you can fulfill a staggering 4 billion 96 million commands.
The M.2 SSD connects to the motherboard in the M.2 slot.
It just slides into the spring-loaded slot and then tightened down with a single screw and that’s pretty much it.
There are no other connections to be made.
So there’s no connection cable or a separate power cable.
So it’s just like an expansion card.
Now not all motherboards are going to have an M.2 slot.
Because like I said before this is a relatively new technology that’s only been around for a few years.
So if you want to use an M.2 NVM Express SSD you need to be sure that your motherboard supports it.
You have to make sure that it has an M.2 slot and that it can support NVM Express technology.
It’s also important to note that not all M.2 SSDs have NVM Express technology or use the PCI Express bus.
Because some M.2’s use the SATA bus, which is a lot slower.