You've bought a bigger, faster NVMe for your PC, and now you're facing the question that stops a lot of people: do you really have to reinstall Windows and set everything up from scratch? The good news is no, you don't. Cloning lets you copy your entire existing drive — Windows, your apps, your settings, your files — onto the new NVMe so it boots up exactly the way it did before. No re-downloading installers, no re-entering licences, no rebuilding your desktop. This walkthrough takes you through the clone path from start to finish, with the back-up-first warnings and the source/target trap spelt out plainly so you don't lose anything.
Before we start, a quick word on why you'd bother. Most people clone when they're moving from a smaller or slower boot drive to a roomier, quicker one — if you're still weighing up whether NVMe is even the right move, our breakdown of NVMe versus SSD versus HDD for Nigerian builds explains where the real speed gains come from, and the best NVMe drives in Nigeria across budget tiers guide helps you pick the right one before you commit to the swap.
Clone or fresh install — which path are you on?
There are two ways to move Windows to a new drive, and they suit different people. Cloning copies everything across so your system is identical afterwards — same apps, same files, same wallpaper. It's the convenience route, and it's what this guide covers. The alternative is a fresh Windows install: a clean slate with none of the clutter your system has accumulated over the years, but it means reinstalling every app and reconfiguring every setting yourself.
If your current Windows has been running for years and feels sluggish or cluttered, a clean install might actually serve you better in the long run. Our guide on when a reinstall versus a reset makes sense walks through that decision honestly. But if your system is healthy and you simply want more space or speed without the hassle, cloning is the sensible choice. Clone equals convenience and keeping everything; fresh equals a clean slate at the cost of setup time.
Prep — the non-negotiables before you touch anything
Cloning is usually a safe, read-only operation on your source drive, but disk operations carry risk and you should never go in unprepared. Get these sorted first:
- Back up first, always. Cloning rarely goes wrong, but "rarely" is not "never", and a power cut mid-clone or a wrong click can cost you. Before any hardware change, follow our pre-swap backup best practice so your important files are safe on a separate drive or in the cloud no matter what happens.
- Have both drives connected at once. Cloning copies from the old drive to the new one, so both need to be plugged in during the process. Fit the new NVMe into a spare M.2 slot on your motherboard — our step-by-step on adding a secondary NVMe covers the physical fitting and BIOS detection.
- Check the form factor and key. Make sure the new drive physically fits and matches your slot. If you're unsure what 2280, 2242 or the notch keys mean, our explainer on M.2 SSD types sorts it out before you order the wrong thing.
- Mind the capacity. The new drive must be at least as large as the used space on the old one — not its total size. You can clone a 1TB drive that's only 300GB full onto a 500GB drive, because the data fits. What you can't do is squeeze more data than the target can hold.
The tooling — what software to clone with
You need a reputable cloning tool, and you have a few solid options. Macrium Reflect has long been a popular choice, with free editions that have served home users well for years. Beyond that, most SSD manufacturers give you their own migration software free — so check the box your drive came in or the maker's website before paying for anything.
- The SSD maker's own tool. Samsung drives come with Samsung Data Migration and Samsung Magician; Crucial has its own cloning utility; some brands bundle a version of Acronis. These are tuned for that brand's drives and are usually the smoothest option.
- Macrium Reflect. A long-standing, well-regarded general-purpose tool that works regardless of drive brand. Its free editions have historically been a go-to for exactly this kind of job.
- Check before you buy. Many people pay for cloning software without realising their drive shipped with a free licence. Look first — you may already have what you need.
The clone process — step by step
With both drives connected and your backup done, the actual clone is straightforward — but the one step you must get right is choosing source and target correctly. Get them the wrong way round and you'll wipe the data you're trying to save.
- Install and open your cloning tool. Run it from your existing, working Windows install.
- Select the source. This is your old Windows drive — the one you're copying from.
- Select the target. This is the new NVMe — the one you're copying to. Double-check this. The target is wiped during cloning, so if you pick them backwards you destroy your original. When in doubt, identify the drives by their size or model number, not just the slot.
- Copy all partitions. Let the tool copy every partition, including the hidden EFI and recovery partitions. These are small and easy to overlook, but they're what makes Windows boot — leaving them out is the single most common reason a clone won't start up afterwards.
- Expand the main partition. If your new drive is larger, tell the tool to expand the Windows partition to fill the extra space. If it can't, you can do this later in Windows Disk Management — otherwise you'll have a big drive with a small usable area and unallocated space sitting idle.
- Run the clone. Start it and let it work. Depending on how much data you have, this can take anywhere from several minutes to well over an hour, so don't interrupt it.
A note on partition layout
It's worth understanding why "copy everything" matters. A modern Windows install isn't one partition — it's several. There's the EFI System Partition that holds the bootloader, a small Microsoft Reserved partition, the main Windows partition where your files and apps live, and usually a recovery partition. A proper clone copies all of them.
When a clone refuses to boot, the cause is almost always that the boot-related partitions were excluded or that the tool only copied the visible Windows partition. If your cloning software offers an option like "clone this disk" rather than "clone this partition", choose the whole-disk option — it brings the hidden boot partitions along automatically and saves you a headache later.
Post-clone boot fix — making the new drive start up
Once the clone finishes, your job is to make the PC boot from the new drive. This is where a little patience pays off:
- Shut down fully. Power off completely before changing anything, rather than restarting.
- Set the new drive as boot device. Enter your BIOS or UEFI (usually Delete or F2 at startup) and move the new NVMe to the top of the boot order. This tells the PC to start Windows from the clone rather than the original.
- Confirm it boots, then deal with the old drive. Boot into Windows from the new drive and check everything is there and working. Only once you're certain should you wipe or remove the old drive — keep it untouched as a safety net until then.
- If it won't boot, check the boot order first. Nine times out of ten, a clone that won't start just means the BIOS is still pointing at the old drive. Confirm the boot order names the new NVMe.
- As a last resort, run a startup repair. If the boot order is correct but Windows still won't load, booting from a Windows install USB and running Startup Repair can rebuild the bootloader. This usually fixes a stubborn clone.
Once the system boots reliably off the new NVMe, the old drive becomes free real estate. Wiped and reformatted, it makes an excellent secondary data drive for games, photos or downloads — our adding a secondary NVMe guide covers setting it up in that role.
Frequently Asked Questions
Can I clone a larger drive onto a smaller NVMe? Yes, as long as the actual data on the larger drive fits within the smaller one's capacity. A 1TB drive holding only 250GB of data clones fine onto a 500GB NVMe. What matters is used space, not total size — if your data exceeds the target's capacity, the clone won't proceed.
Will I have to reactivate Windows after cloning? Usually not. Because cloning produces an identical copy on the same PC, Windows generally stays activated. If it does flag activation, it's normally resolved by signing in with your Microsoft account or running the activation troubleshooter, since the digital licence is tied to your hardware.
Why won't my cloned drive boot? The two usual culprits are the BIOS boot order still pointing at the old drive, or the boot partitions being excluded during the clone. Check the boot order first, then confirm you cloned the whole disk rather than a single partition. A Startup Repair from a Windows install USB fixes most remaining cases.
The One Thing to Remember
If you take away nothing else, take this: back up first, and triple-check which drive is the source and which is the target. Cloning is a reliable way to move Windows without losing a thing, but the one mistake that bites people is getting source and target backwards and wiping the drive they meant to save. Keep the old drive untouched until the new one boots perfectly, and you've got a guaranteed safety net.
Not sure your new NVMe is the right fit for your motherboard, or want us to handle the whole migration for you? Build your ideal setup with our configurator, or get in touch and we'll advise on the right drive and do the clone properly so you boot up faster with everything exactly where you left it.