Running out of room for games, photos, or work files? You can add more PC storage by connecting an external drive, installing an additional internal drive, or replacing your existing drive with a larger one.

The right approach depends on your computer’s connections and what you want to achieve. More space for files is a different goal from making your Windows C: drive larger.

Here is where to start:

• Want extra space without opening your PC? Connect an external drive.

• Want more internal capacity while keeping your current system drive? Check for a compatible spare storage connection.

• Have no suitable spare connection, or need a larger system drive? Consider replacing the existing drive.

This guide covers choosing a drive, checking compatibility, installing it, and putting the extra capacity to use in Windows.

Compare Your Storage Upgrade Options

Adding another drive usually creates a separate storage location. It does not automatically expand C: or move existing files.

Storage is also different from RAM. Storage holds your files and installed software; adding RAM does not increase the space available for them.

Choose Between an SSD and HDD

There are two separate decisions to make: internal or external describes how a drive connects, while SSD or HDD describes its storage technology.

An SSD is generally the better starting point for Windows, frequently used applications, and games where loading performance matters. An HDD remains worth comparing for large collections of less frequently accessed files, particularly when capacity and current cost are your main considerations. Kingston’s SSD and HDD comparison explains the underlying differences.

Do not select a drive solely by its advertised maximum speed. Your computer’s connection, the cable or enclosure, the source drive, and the files being transferred can all affect results.

How much capacity do you need?

In Windows 11, open Settings > System > Storage to review current usage.

Estimate the files and applications you expect to add, then leave room for growth. If you are replacing an existing drive, choose enough capacity for the data you will keep and any migration-tool requirements.

Check Compatibility Before Buying

Find your PC’s exact model. For a custom desktop, identify the motherboard and case. Use the manufacturer’s specifications and service manual to answer the following questions.

Is there a spare connection and enough space?

An additional internal drive needs a compatible connection and a secure mounting location.

Depending on your computer, this could mean:

• An unused M.2 storage slot.

• A SATA connection and a suitable drive bay.

• An available SATA power connector.

• A model-specific laptop connector or caddy.

Laptop storage layouts vary. Some support a second drive, others allow replacement only, and some have storage that is not user-upgradeable.

Does the drive match the supported interface and size?

For M.2 SSDs, confirm the supported length, protocol, and clearance.

“M.2” describes a form factor. An M.2 drive may use SATA or PCIe, and the computer’s slot must support the appropriate protocol. Physical fit alone does not establish compatibility. See Kingston’s SSD compatibility FAQ.

For SATA drives, check the supported size, thickness, and mounting arrangement. A desktop SATA installation typically needs separate data and power connections; a laptop may use a dedicated assembly.

For external storage, confirm the connector and supported connection speed. A matching connector shape alone does not tell you the transfer speed you will achieve.

For a USB-C external SSD, see our guide to USB-C cable labels and data speeds to understand which specifications to check on the cable.

Do you have the necessary accessories?

Check what comes with the drive. Depending on the installation, you may also need:

• A SATA data cable.

• A mounting bracket or laptop caddy.

• An M.2 screw or retention hardware.

• A compatible enclosure or adapter for migration.

Resolve these requirements before ordering.

Option 1: Connect an External Drive

An external drive is a straightforward way to add capacity without opening your computer.

1. Connect it

Use the supplied cable or a compatible replacement. Connect a power adapter if the drive requires one.

2. Check that Windows recognizes it

Open File Explorer > This PC and look for the drive.

Many external drives arrive ready to use. If you can save and open files, you do not need to initialize or format the drive simply because it is new to your PC.

If Windows asks to format a drive that contains files you need, stop before accepting. Formatting can erase its contents.

3. Copy and verify files

Copy a small group of files first, then open several from the external drive.

Keep a separate backup of important data. Moving your only copy to a different drive frees space but does not create a backup.

4. Save suitable new content there

Choose the external drive when saving files or setting an application’s download location. Files stored there will be unavailable while it is disconnected.

For games and applications, use supported installation or migration tools. Manually moving an installed program folder can prevent it from working.

Check your result: The drive appears in File Explorer, and a test file can be saved, closed, and reopened.

Option 2: Add an Internal Drive

An additional internal drive lets you keep Windows on the existing drive while adding a separate place for files, games, or applications.

Back up important files before starting. Follow the manufacturer’s instructions for shutdown, power disconnection, battery handling, and protection against static electricity.

The following steps describe the general process. Your computer or motherboard manual determines the exact procedure.

Install an M.2 SSD

1. Locate the compatible, unused M.2 storage slot.

2. Remove the cover or heatsink, if fitted.

3. Confirm that the mounting position matches the SSD’s length.

4. Insert the SSD as directed in the manual.

5. Secure it using the correct screw or retention mechanism.

6. Reinstall any heatsink or cover according to the instructions.

Handle the drive by its edges. Do not force it into the slot or overtighten screws.

Follow the manufacturer’s directions for thermal pads. Check the motherboard manual for any restrictions caused by shared resources between storage connections.

Install a SATA SSD or HDD in a desktop

1. Secure the drive in a suitable bay or bracket.

2. Connect a SATA data cable between the drive and motherboard.

3. Connect SATA power from the power supply.

4. Check that connections are secure and cables are clear of fans.

5. Close the case and reconnect the computer.

Laptop SATA installations can use different connectors and mounting arrangements. Follow the model-specific service instructions.

Set up a new, blank internal drive in Windows

After installation, start Windows and check File Explorer. A new, blank drive may need setup before it appears.

Use the following process only for a new, empty drive. If a drive should contain data but appears uninitialized or unallocated, investigate before making changes.

1. Right-click Start and select Disk Management.

2. Identify the new disk using its capacity and available disk information. Do not assume it will always be “Disk 1.”

3. If the disk is offline, bring it online. If it is marked Not Initialized, right-click its disk label and select Initialize Disk.

4. Choose the appropriate partition style. GPT is generally suitable for modern Windows PCs; check any system-specific requirements.

5. Right-click the new disk’s Unallocated space and select New Simple Volume.

6. Follow the wizard to choose the volume size, assign a drive letter, and format it.

If the disk is already initialized, skip initialization. If a usable volume already exists, do not recreate or format it unnecessarily.

NTFS is a common choice for a drive used primarily with Windows. Give the volume a recognizable label, such as “Games” or “Projects.”

Administrator permissions may be required. Microsoft provides instructions for initializing a new disk and managing disks and volumes.

Check your result: The new volume appears with the expected capacity and drive letter, and you can save and reopen a test file.

Option 3: Replace Your Existing Drive

Replacing a drive may be appropriate when your computer has no suitable spare connection or you want a larger Windows system drive.

First, determine whether the drive contains Windows.

Replacing a data-only drive

Back up its contents, install the replacement using the manufacturer’s instructions, and set up the new drive if necessary. Then restore your files.

Applications installed on the old drive may require migration or reinstallation.

Replacing the Windows drive

Choose between two approaches:

• Clone the drive: Use compatible migration software to copy Windows, the required system partitions, applications, and data.

• Reinstall Windows: Install Windows on the new drive, reinstall applications, and restore your files.

Cloning requires a way to connect the source and destination during migration. This may involve a spare internal connection or a compatible enclosure or adapter.

Check the migration tool’s requirements for capacity, partition layout, and encrypted drives. Copying visible files through File Explorer does not create a bootable Windows replacement.

Before making changes, verify that your backups are accessible. If BitLocker or device encryption is enabled, confirm that you can retrieve the recovery key: hardware changes can trigger a recovery prompt. Microsoft explains how to find your BitLocker recovery key.

Follow the computer and migration-tool instructions for starting from the replacement.

Check your result: Windows starts from the new drive, your files and applications work, and the additional capacity is usable. Keep the original drive intact until you have verified the replacement.

Put Your New Storage to Use

Installing a drive does not automatically move existing content. Decide what belongs on the new storage and update your save locations.

Move personal files

Copy suitable documents, photos, videos, and project files to the new drive. Check the copies before removing originals, and maintain a separate backup for important content.

Move games and applications through supported tools

Use the launcher’s library-management feature or the application’s migration instructions. If migration is unsupported, reinstalling to the new drive may be necessary.

Do not manually move Windows system folders or installed program directories.

Change where new content is saved

In Windows 11, go to:

Settings > System > Storage > Advanced storage settings > Where new content is saved

Choose a destination for the available content categories. Individual applications may have their own save or download settings, so check those as well. Changing a default does not automatically relocate existing content. 

What If Your C Drive Is Full?

Adding a second physical drive increases total capacity, but it does not automatically make C: larger.

For example, a new drive may appear as D: while C: remains unchanged. Moving suitable files and supported applications to D: can relieve pressure on C:.

If you need to expand C: itself, a larger system-drive replacement may be appropriate. Extending a basic volume in Disk Management requires suitable unallocated space immediately after it on the same disk, along with other conditions. A second physical drive does not supply that adjacent space. 

Frequently Asked Questions

Why is my new drive not showing up?

Check the physical connection and any required power supply, then look in Disk Management.

A new, blank internal drive may need initialization and a volume. If it is missing from Disk Management too, check whether the computer’s firmware detects it and revisit compatibility.

For an external drive, try another suitable port and a compatible cable. Avoid initializing or formatting a drive containing existing data as a routine troubleshooting step.

Can I add more storage to any laptop?

It depends on the model. Check the manufacturer’s service manual for spare slots and replacement options. External storage may be an option when internal expansion is unavailable.

Do I need to reinstall Windows?

Usually, no, when adding a separate storage drive and keeping Windows on the original drive.

When replacing the Windows drive, you must migrate the system or install Windows on the replacement.

Will adding storage make my PC faster?

Adding capacity gives you more room. Performance changes depend on the drive, connection, workload, and where Windows and applications run.

A second drive does not automatically accelerate software that remains on the original drive.

Can I install games on an external drive?

Check the game and launcher requirements. Some support external storage, but performance depends on the drive and connection. The drive must remain connected during use.

Does cloud storage add PC storage?

Cloud storage does not add physical capacity to your computer. It can reduce local usage when the service supports keeping files online without retaining full local copies. The result depends on synchronization and file-retention settings.

Start With Your PC’s Storage Specifications

Find your PC or motherboard model and check its storage specifications before buying an internal drive. Confirm the supported interface, drive size, available connections, and required accessories.

Choose an external drive for a simple capacity addition, another internal drive where supported, or a larger replacement when you need to upgrade the existing drive. After installation, verify that it works and update your save locations so the new space becomes useful.

If you are also considering replacing your computer rather than upgrading it, explore Mini PCs with a 1TB SSD. Check the selected configuration and its future storage-expansion options before buying.