Which SSD should I buy?
Many customers prefer SSDs for their speed, reliability, and durability. However, they are often faced with challenges when deciding which SSD to purchase. Not all solid state drives are the same. Some are faster than others, and some will refuse to work (or work at a limited capacity) on your existing hardware.
There are many differences between SSDs. The main things you should be looking out for include:
- Form factor: the physical dimensions of your SSD determines where it can fit on existing computers. There are many dimensions for SSDs:
- 2.5" SSDs
- M.2 SATA and NVMe SSDs (4 different types)
- mSATA SSDs
- SATA or NVMe: SATA drives can only reach a maximum of 600Mbps transfer speeds. NVMe drives are newer and up to 7x faster.
- Write Cycles: this determines how much data an SSD is designed to handle in it's lifetime. All SSDs have a finite life cycle, but they are typically rated to last at least 10 years (or more) of average consumer use.
Differences between SSD types will be explained further below.
Key Differences Between NVMe and SATA SSDs
SSDs can use one of two methods for communicating with your PC: SATA, and NVMe. SATA is an older standard, and slower than NVMe. While SATA SSDs can transfer data at a theoretical maximum rate of 600Mbps, NVMe SSDs can attain speeds of 7.5Gbps.
SATA and NVMe SSDs can come in different form factors. SATA drives can come in 2.5", M.2 or mSATA form factors. NVMe drives, on the other hand, are typically only used with an M.2 form factor.
Form Factors: 2.5", M.2 and mSATA
You often hear of M.2 SSDs, or mSATA SSDs. What do they mean, and how important are they?
M.2, mSATA and 2.5" refer to different SSD form factors. You may only use an M.2 drive in an M.2 slot, for example.
- M.2 SSDs: These SSDs are commonly used in laptops. They are small in size, and can communicate either using SATA or NVMe. It's important to check if your M.2 socket is compatible with both SATA and NVMe drives (some are only compatible with one or the other). To check, refer to the diagram below.
- M.2 SATA SSDs are "B + M" keyed, while M.2 NVMe SSDs are only "M" keyed
- mSATA SSDs: mSATA was originally the smallest SSD form factor. It was the precursor to M.2, which succeeded the mSATA format. As the name implies, mSATA SSDs use the SATA interface for communication. This limits their transfer speeds to 600Mbps. Since its replacement by the newer (and faster) M.2 standard, mSATA SSDs are rarely found in today's market.
- 2.5" SSDs: A 2.5" SSD is physically larger than an M.2 or mSATA SSD, but smaller than a 3.5" traditional hard drive. All 2.5" SSDs are SATA, and thus are limited in speed (though still much faster than a traditional spinning mechanical drive). The image below demonstrates how 2.5" SSDs look like:
