Move your OS or games to an SSD

Steps

1. 01

   Buy the right drive

   • Check what your machine physically takes before you buy anything
   • An M.2 slot on the motherboard takes NVMe; a 2.5-inch bay takes SATA. A desktop usually has both, many laptops only one M.2 slot
   • M.2 drives come in different lengths — 2280 is by far the most common — and your manual or the maker's spec page lists which lengths the slot accepts
   • For the drive Windows lives on, prefer NVMe (M.2) — several times faster than SATA for about the same price per gigabyte
   • Only a 2.5-inch bay? A SATA SSD is still an enormous upgrade over any hard drive. Don't skip the upgrade because it is 'only' SATA
   • Size it at 500 GB or more if it will hold Windows and games, and leave room: an almost-full SSD slows down
   • If you move large files often (video, virtual machines), compare sustained write speed rather than peak read speed — that is the number that describes a long copy

   Why?

   TLC drives are the usual sweet spot for price against endurance. QLC drives are cheaper and fine for storage, but they lean harder on a fast cache — once a long write exhausts it, the speed drops away sharply.

2. 02

   Back up before you touch anything

   • Make a full backup to a separate drive and check you can open a file from it
   • If the new SSD is smaller than the old drive, shrink the old Windows partition to fit first — Win+XDisk Management›right-click the partition›Shrink Volume

   !Careful: This fix ends with a drive swap and is marked irreversible for a reason: a clone that goes wrong can leave neither drive bootable. The backup is what makes that an inconvenience instead of a disaster.

   Why?

   An SSD smaller than the source is the single most common reason a clone refuses to start afterwards.

   Also see: Back up properly (3-2-1 rule)

3. 03

   Clone the whole drive, not just C:

   • Use the SSD maker's own free cloning tool, from the brand you actually bought
   • Most major SSD makers publish one on their support site, and it is usually free only for their own drives — using the matching brand avoids a licence prompt halfway through
   • Connect the new SSD alongside the old drive (a USB-to-SATA or USB-to-NVMe adapter is fine for a laptop)
   • Choose the whole disk as the source, not the C: partition

   ✓You should see: The tool reports the clone finished with no errors, and the new drive shows the same partitions as the old one in Disk Management.

   !Careful: Cloning only C: produces a perfect copy of your files that will not boot. The small hidden EFI and recovery partitions are what make a disk startable, and they are not part of C:.

4. 04

   Swap the drives and boot once, carefully

   • Power off, unplug at the wall, and fit the SSD — for a desktop also physically disconnect the old drive for this first boot
   • In UEFI, set the SSD as the first boot device, and make sure SATA mode is AHCI (or that NVMe is enabled) before you save and exit
   • Boot, and let Windows settle for a few minutes before judging anything

   !Careful: Leaving the old drive connected for the first boot is how people conclude the clone failed: the boot manager can start from the new drive while still pointing at the old one, so you end up running the old install without realising.

   Why?

   If Windows stops with INACCESSIBLE_BOOT_DEVICE, the drive is usually fine — it is the SATA/NVMe mode in UEFI that is wrong.

   Also see: Know your BIOS settings (the 5 that matter)

5. 05

   Verify, then leave the old drive alone

   • Confirm Windows boots from the SSD and that your files, apps and licences are all present
   • Reconnect the old drive only after the SSD has booted cleanly on its own
   • Leave the old drive untouched for a month before you wipe or reuse it

   ✓You should see: Boot takes seconds rather than minutes, and Task Manager → Performance shows the SSD as the system drive.

   !Careful: Don't wipe the old drive the same day. It is your only way back, and the things that turn out to be missing — a licence key, a save folder, a mail archive — surface in week three, not on day one.