NVMe SSDs

Drives on the PCIe bus, where the interface stops being the limit and the controller starts to matter.

An NVMe drive talks to the processor over PCIe rather than through a storage controller, which is why the read speeds here are several times what any SATA drive reaches. Within the class the spread is wide: generation, controller and whether the drive carries its own DRAM cache separate one NVMe drive from another far more than capacity does.

What an ordinary nvme ssd looks like

Medians, with values beyond 1.5× the interquartile range excluded so one listing cannot move them. A class holding fewer than 8 drives publishes no baseline at all.

How this class is distributed

63 drives in this corpus sit in this class. By capacity:

The generation of the slot decides the speed, not the drive

An NVMe drive runs over PCIe lanes, and each generation of PCIe roughly doubles the bandwidth available. A drive rated for the current generation put into an older slot runs at the older slot’s speed, and no part of the listing will warn you. This is the single most common reason a new drive benchmarks at half its advertised figure: the drive is fine and the slot is the constraint. Check the motherboard or laptop specification for the generation of the M.2 slot before paying for headline numbers the machine cannot carry.

Why the write figure is so much lower than the read figure

Read and write speeds diverge sharply in this class, and the reason is caching. Most consumer drives write incoming data quickly into a fast buffer and move it to slower, denser storage afterwards. Short bursts see the headline figure; a sustained transfer large enough to fill the buffer falls to the drive’s real write rate, sometimes by a large factor. The listed write speed is therefore a burst figure, and for anyone regularly moving very large files it is the least representative number on the box.

Drives without their own memory

Controllers keep a map of where data physically sits, and the fastest drives hold that map in dedicated memory on the drive. Cheaper ones do not, and either borrow a slice of system memory or read the map from the flash each time. In everyday use the difference is modest; under sustained random access it is not. Listings rarely state this plainly, so the practical signal is price: a drive materially cheaper than its neighbours at the same capacity and rated speed has usually saved the money here.

Heat is a specification these drives do not publish

A fast NVMe drive under sustained load gets hot enough to throttle itself, which is the controller protecting the flash rather than a fault. In a desktop with airflow this rarely bites; in a thin laptop or a console it can. A heatsink is cheap and effective where one fits, and where it does not, the honest expectation is that long transfers will slow down partway through. Nothing in the specification table describes this, and it is the difference between the benchmark figure and the figure you get.

What the speed actually costs

The interesting comparison is against SATA rather than within this class. An NVMe drive here reads many times faster than a SATA one for a price per terabyte that is only marginally higher — a far smaller premium than the gap between the cheapest and dearest SATA drives. If the machine has a free M.2 slot, choosing SATA to save money is optimising the wrong variable. If it does not, none of this class is available at any price, which is the other half of the same fact.

Endurance, and the number that is easy to over-worry about

SSDs are rated in terabytes written, and the figure sounds alarming until it is divided by a realistic write rate. A rating of a few hundred terabytes written, against a typical desktop workload of a few tens of gigabytes a day, is measured in decades rather than years. Endurance matters where writes are genuinely heavy — video capture, a busy database, a drive used for constant large transfers — and for most machines the drive is replaced for being small long before it is worn out. The warranty usually expires at whichever comes first, so it is worth reading both numbers together.

Why the capacity you get is smaller than the one you bought

Drive manufacturers count a terabyte as a trillion bytes; operating systems generally count it as 2^40, about ten per cent more. A 1 TB drive therefore shows as roughly 931 GB before a single file is written, and nothing is wrong. Some SSDs also reserve a further slice as spare area for wear levelling, which the controller uses and the operating system never sees. Neither figure appears on a listing, and together they are the most common reason a new drive looks short on arrival.

Not every M.2 slot carries NVMe, and not every M.2 drive is one

M.2 is a shape, not an interface. Some M.2 slots carry PCIe and some carry SATA, some carry either, and drives exist in both kinds looking almost identical — this corpus contains SATA drives in exactly the same 2280 form factor as the NVMe ones. A SATA M.2 drive in a PCIe-only slot does not work at all; an NVMe drive in a SATA-only slot does the same. The keying notch differs and is the physical tell, but the reliable check is the machine’s documentation for what that specific slot supports, done before ordering rather than after.

Warranty is stated less often than you would expect

Only a minority of drives here publish a warranty, and those that do generally offer several years. That silence is worth reading. A drive rated for high sustained speeds is making a claim about its controller and flash, and a manufacturer confident in both usually says how long it will stand behind them. Where the specification table is detailed about performance and quiet about cover, the omission is a choice rather than an oversight, and it is the cheapest thing on the page to check before buying.

Reading these figures

Every number above is a median of what manufacturers publish, not a measurement we took. Where a specification is missing from this table it is because too few listings in the class stated it for a median to mean anything — that is a fact about the listings, not about the drives.

Narrow this class by capacity and budget in the ssd finder.

Computed from the corpus on 2026-08-29.