What does a faster storage device affect?

I have a Desktop computer with a decent 1TB Samsung regular SSD drive. It starts very quickly and runs very quickly. It used to have hard drives and the difference in startup and run is very noticeable.

I have a Laptop that came with a 1 TB NVMe drive in an M.2 slot. It has always been very fast.

I frequently put the laptop on a table across from the Desktop. Once a Feature update has downloaded (Desktop on wired Ethernet ; Laptop on wireless), the installation of the update including restart is pretty much the same.

You might see some speed increase if you upgrade, but it may not be really noticeable.

You might leave this project to the next computer.

The speed of a storage device affects how long things take to load. Whether it's how long it takes your OS to boot up and log in, load stuff in games, moving large amounts of files, etc.

Unless your SSD is performing really bad for some reason, you won't see much of a difference going from an SSD to an M.2 NVMe SSD. With most real world scenarios, the speed difference between the NVMe SSD and the 2.5" SSD is tenths or hundredths of a second.

In some cases, like loading a specific game, the NVMe might be a second or two faster.

You would only see a large upgrade in speed if you were coming from an HDD or a SSHD hybrid drive.

There are two standards for M.2 SSDs: SATA and NVMe.

With SATA, the only difference is the form factor and the shape of the connector. The signaling and expected performance are exactly the same.

With NVMe, the transfer between SSD and mainboard can be faster as there are more parallel lanes on the connector, but for that to be relevant, a number of things need to come together:

1. all of the lanes need to be connected
2. the flash memory needs to be faster than the link speed
3. your workload must be limited by transfer speed

For normal desktop use, the last point is usually the most relevant: loading an OS requires lots of small transfers and the CPU arranging the data in memory in a way that will be useful later. Any complex processing like encoding videos is limited by the CPU as well.

So you would see a difference only if your M.2 SSD is NVMe, not SATA, and you are doing things that require raw throughput with no processing of the data, which in a desktop scenario is basically how fast you can suspend to disk when you have a memory hog application like Photoshop open. So I wouldn't bother.