Read on 2026-10-16. The post was published on May 7, 2024. Speed figures are the ceilings it quotes, not results from a drive in your computer.
What a SATA SSD is
Backblaze, in its post “What's the Diff: SSD vs. NVMe vs. M.2 Drives” (May 7, 2024), says that a Serial Advanced Technology Attachment (SATA) is the standard storage interface used in many computers. It adds that a SATA SSD is an SSD equipped with a SATA interface to connect the storage device to a computer's motherboard. It also says that the SATA SSD comes in the standard 2.5 inch form factor and has both power and data (SATA) connectors. The same post says that if you buy an SSD external drive to connect to your PC, there will most likely be a SATA SSD inside.
What NVMe is
The same post says that non-Volatile Memory Express (NVMe) is a storage protocol that offers high-speed and efficient communication between a computer's CPU and SSDs. It adds that drives that use NVMe were introduced in 2013 to attach to the Peripheral Component Interconnect Express (PCIe) slot directly on a motherboard instead of using the traditional SATA interface typically used by HDDs and older SSDs.
SATA and NVMe in a table
The chart in the same post compares the two like this.
| Feature | SATA | NVMe |
|---|---|---|
| Bus | SATA bus | PCIe bus |
| Data transfer speed | Slower (up to 600 MB/s) | Faster (typically 3000 MB/s and up to 7,500 MB/s) |
| Latency | Higher | Lower |
M.2 is a shape, not a speed
Backblaze, in the same post, says that m.2 is a form factor, which refers to the standard size of a component. It adds that m.2 drives can use either SATA or NVMe to connect to the motherboard, so they have the potential to be much faster when they use the latter. It also says that SATA M.2 drives and 2.5 inch SSDs provide the same level of speed, so to gain a performance increase, you will have to opt for the NVMe-connected drives. The same post says that the mSATA form factor is compact like M.2, but they are not interchangeable, and mSATA drives currently only support the SATA interface.
Checks before you buy
Backblaze, in the same post, says that you should check the capability of your system before choosing a drive, as some older devices don't have the components needed for NVMe connections. It adds that before you buy an M.2 SSD, you'll need to know which interface your computer will accept, M.2 SATA or M.2 PCIe. It also says that if your motherboard does not have an M.2 slot, you may be able to use an M.2 drive by using an adapter card that fits into a PCIe slot. The same post says that while NVMe SSDs are going to be much faster than SATA drives, you may also need to upgrade your processor to keep up or you may experience worse performance. It adds that you should remember to check read and write speeds on a drive as some earlier generations of NVMe drives can have different speeds. It also says that most M.2 drives top out at 2TB, although some may be available as 4TB and 8TB models.
If the drive is going into a NAS
Backblaze, in the same post, says that if you are adding an SSD to your NAS array, you should always double check your NAS specs before you commit to a purchase. It adds that there are several use cases where you'd see minimal advantage compared with an HDD, such as if you want a NAS to store large amounts of infrequently accessed files (i.e. in backup/archive scenarios).
Transfer time from a spec-sheet speed
Copy time
Type the size of what you copy and the speed from the drive's spec sheet.
- Time at that speed
Plain arithmetic with 1 GB = 1000 MB. A real copy runs at the speed of the slowest link, and the number you type is not a measurement of your drive. Nothing you type leaves your browser.
Sources
Checked on 2026-10-16 against Backblaze: What's the Diff, SSD vs. NVMe vs. M.2 Drives. Read the source again before you rely on a number, because posts get updated and drive models change.
Related guides
- SSD vs HDD for home storage: How the two drive types differ, from the source's own comparison.
- SSD lifespan: TBW and P/E cycles: How to read endurance numbers on a spec sheet, with a write-budget calculator.
- NAS or external hard drive: What each one is and what neither protects against.