Solid-state drives for laptops, desktops and servers: when to replace and how to match one

Replace a solid-state drive when it reports errors or heavy wear through its health monitoring, turns read-only, disappears from the system, or slows sharply. Back up first if you still can. The right replacement matches the interface, the form factor and, for a server, the drive carrier and the server maker's own part number.

Also called: SSD, solid-state drive, solid state disk, flash drive, NVMe drive, M.2 drive, SATA SSD, SAS SSD, U.2 drive, server SSD, hot-plug drive

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What a solid-state drive is

A solid-state drive stores data in flash memory chips managed by a small controller, with no moving parts. That makes it faster, quieter and more tolerant of knocks than a spinning hard drive. Laptop and desktop drives are usually small cards that plug straight into the board, or drives the size of a laptop hard drive. Server drives usually sit in a hot-plug carrier that slides into a drive bay at the front of the server.

How do you know the drive is failing?

Flash memory wears a little every time it is written, and drives keep count. Their health monitoring, often called SMART, reports the wear level and errors, and server management tools raise alerts from it. Signs that a drive needs replacing:

  • The health monitoring or the server's management tools report predictive failure, high wear or a growing error count.
  • The drive switches itself to read-only, which some drives do at the end of their life to protect the data.
  • The drive disappears from the system, or is detected only some of the time.
  • The machine freezes, or files become corrupted or fail to open.
  • The drive becomes much slower than it used to be.
  • In a server, the drive's status light shows a fault, or a RAID array reports the drive as failed or degraded.

First, protect the data

If the drive still works, copy your data off it before anything else. In a server with a RAID array, replace a failed drive promptly, because the array has no protection left until it has rebuilt onto the new drive.

How to choose the right drive

  • Match the interface. SATA, SAS and NVMe drives are not interchangeable, even when they look alike.
  • Match the form factor. Card-style drives come in different lengths and keyings, and bay drives come in different sizes and thicknesses.
  • For a server, match the carrier, also called a tray or caddy. Drives are usually supplied in the server maker's carrier, which differs between server generations.
  • For a server, also use the server maker's part number. HPE, for example, lists an option part number for ordering and a spare part number for service replacement, and either identifies the same drive. The label on the drive or its carrier may show one of them, or another assembly number. Some servers warn about drives that are not on their supported list.
  • Choose a capacity at least as large as the drive being replaced. In a RAID array, a smaller drive cannot replace a larger one.
  • Check the drive's intended use. Server drives are rated for different amounts of writing per day, often described as read-intensive, mixed-use or write-intensive. Replace like with like in an array.

Fitting tips

  • In a laptop or desktop, shut down, unplug and disconnect the battery before fitting the drive.
  • Card-style drives are held by a single small screw or a latch at the far end. Keep the screw, because a new drive rarely comes with one.
  • In a server, check the bay number and the drive's fault light before removing anything, so you pull the failed drive and not a working one.
  • After fitting, check that the array starts rebuilding, or that the operating system sees the new drive.

Common questions

Can I replace a hard drive with a solid-state drive?

Often yes, if the interface and size match the bay. In servers, choose a drive the server maker lists for that model and carrier.

Can I put a larger drive in my RAID array?

Usually yes. The array keeps to the capacity of the drive it replaces until every drive in it has been replaced. A smaller drive will not work.

What do the option and spare part numbers mean?

Some server makers order a drive under one number, the option part number, and label it with another, the spare part number. Both refer to the same drive, and either one helps us match it.

How long does a solid-state drive last?

It depends on how much data is written to it. Most desktop and laptop drives are rated for far more writing than everyday office use needs. Server drives are rated for a stated amount of writing, and their health monitoring shows how much of it has been written so far.

What is the difference between an M.2 SATA and an M.2 NVMe drive?

Both have the same small M.2 card shape, but they talk to the computer differently. NVMe drives are much faster and need a slot that supports NVMe, while SATA drives need a slot wired for SATA. The notch on the connector often differs too. Check what your slot supports before choosing.

Will I need to reinstall the operating system on a replacement drive?

Yes, unless you copy, or clone, the old drive onto the replacement first. Cloning needs the old drive to be readable and the replacement to be at least as large as the data on it. Back up your files before any drive change.

Find your SSD

Not sure which one you need? Send us the number from the label, or your machine's serial number, and we will confirm the match before you order. Ask us to find a part

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