How to properly install drive D on a laptop: 3 working methods

You just bought a new laptop and discovered that the entire hard drive capacity has been “eaten up” by the system partition C:? Or did your old laptop start to slow down due to lack of space on the main disk? Dividing the drive into two sections - C: (for the system) and D: (for files) - solves both problems. But how to do it no data loss And without reinstalling Windows?

In this article - three proven ways to create disk D on a laptop, including step-by-step instructions for beginners and optimization tips. We'll figure out how to choose the right partition size, what tools to use (built-in Windows and third-party), and what to do if drive D suddenly “disappeared” after a system update. And also - a table of compatibility of methods with different types of drives (HDD, SSD, NVMe) and answers to frequently asked questions.

Why do you need drive D on a laptop: 5 reasons to crash your hard drive

Many users store all files on one partition for years C:until the system begins to choke. Partitioning the disk into C: And D: - not a whim, but a practical solution. Here's why:

• 🔄 Data Security: If Windows crashes or is attacked by a virus, you can reinstall the system to C:without touching the files on D:.
• ⚡ Performance: The system partition is not clogged with temporary files and program caches (for example, Photoshop or games).
• 📁 Ease of sorting: Music, movies, documents and backups are stored separately from system files.
• 🔧 Easy recovery: When updating Windows to a new version (for example, from Windows 10 to 11) the risk of losing personal data is minimal.
• 💾 SSD optimizationNote: For SSDs, it is recommended to leave 10-15% free space to extend the lifespan.

But there are also nuances. For example, on laptops with SSD volume 128–256 GB the breakdown may be redundant - it is better to use an external drive. And if you have HDD on 1 TB and more, disk D: will be a salvation for archives and difficult projects.

Method 1: Partitioning the disk through Disk Management (without programs)

The safest method is to use the built-in Windows utility. It is suitable for HDD And SSD, but has a limitation: You can shrink a volume only if there is free space on drive C: (minimum 10–15% of the volume of the new section).

Instructions for Windows 10/11:

1. Click Win + X and select Disk management.
2. In the list of drives, find Disk 0 (usually this is the system C:) and right-click on it → Shrink Volume.
3. In the field Size of compressible space indicate the volume for D: in megabytes (for example, 200,000 MB = ~200 GB). Windows will automatically show the maximum possible size.
4. After compression, unallocated space will appear (black block). Right click on it → Create a simple volume.
5. Follow the wizard: assign a letter D:, select file system NTFS and format the volume.

⚠️ Attention: If the button Shrink Volume inactive means:

• The disc is damaged (check with chkdsk C: /f on the command line).
• On disk C: there is no free space (free up at least 20 GB).
• Using an outdated file system FAT32 (need to be converted to NTFS).

Method 2: Partitioning using DiskPart (for advanced users)

Utility DiskPart is a powerful command line tool that allows you to partition disks without a GUI. This method is useful if Disk Management refuses to shrink the volume or you need to create a partition with specific parameters (for example, for Linux or macOS in dual-boot).

Step by step instructions:

1. Запустите командную строку от имени администратора (Win + X → Терминал (администратор)).
2. Введите команды по порядку:
diskpart
list disk          // Посмотрите номер диска (обычно Диск 0)
select disk 0      // Выберите системный диск
list partition     // Проверьте разделы
select partition 1 // Выберите раздел C: (обычно Раздел 1)
shrink desired=200000 // Сожмите на 200 ГБ (указывайте в МБ!)
create partition primary
format fs=ntfs quick
assign letter=D    // Назначьте букву D:
exit

⚠️ Attention: If after the command shrink error appears "There is not enough space to perform the operation", means:

• On disk there is non-movable files (For example, hiberfil.sys or pagefile.sys). Disable hibernation (powercfg /h off) and try again.
• The disk is fragmented. Run defragmentation (dfrgui in the menu Win + R).

Method 3: Third-party partitioning programs (AOMEI, MiniTool, EaseUS)

Windows built-in tools don't always do the job. For example, they cannot:

• 🔄 Move non-movable files automatically.
• 📏 Resize partition no data loss (if there are already files on the disk).
• 🖥️ Work with GPT-disks older than 2 TB.

In such cases, third-party programs will help. We tested three popular solutions:

Program	Free version	SSD/NVMe support	Features
AOMEI Partition Assistant	Yes (with restrictions)	✅	Moves system files, supports UEFI.
MiniTool Partition Wizard	Yes (up to 1 TB)	✅	Can convert MBR → GPT without data loss.
EaseUS Partition Master	No (30-day trial)	✅	Supports dynamic disks and RAID arrays.

Instructions with example AOMEI Partition Assistant:

1. Download and install the program from official website.
2. Run the utility, select the drive C: → Resize partition.
3. Drag the slider to the right to make room for D: (recommended size is 30–50% of the total disk volume).
4. Click Apply → Go and wait for it to complete (the laptop will reboot).

What to do if the program freezes at the "Applying changes" stage

If AOMEI or MiniTool freezes while applying changes for more than 30 minutes:

1. Do not forcefully terminate the process - this may damage the file system.

2. Wait 1–2 hours (on a HDD with a capacity of 1+ TB, the operation may take a long time).

3. If the laptop does not respond, hold the power button for 10 seconds to perform a hard shutdown. After turning on, run disk check (chkdsk /f).

Optimal D drive size: how much space to allocate?

There is no universal answer, but there are proven recommendations:

• 🎮 For games and programs: 300–500 GB (modern games like Call of Duty: Warzone occupy up to 200 GB).
• 📷 For photo/video: 500 GB–1 TB (files RAW and video in 4K weigh tens of gigabytes).
• 📄 For documents and music: 100–200 GB (enough for 50,000 songs in MP3).
• 🔄 For backups: 20–30% of the system disk volume (for example, if C: for 256 GB, allocate 60–80 GB for backups).

📌 Key Principle: on the system disk C: must remain minimum 20% free space for stable Windows operation. If you have SSD by 256 GB, it is optimal to split it like this:

• C: — 120–150 GB (system + programs).
• D: — 80–100 GB (files and backups).
• Unallocated — 10–20 GB (for future needs).

Common problems and their solutions

Even with the right actions, errors can occur. Here are the most common ones and how to fix them:

Problem	Reason	Solution
Drive D doesn't show up in This PC	No letter assigned or partition not formatted	Open Disk Management, click on D: → Change drive letter or Format.
"Not enough space to compress" error	Unmovable files or fragmentation	Disable hibernation (powercfg /h off), swap files and run defragmentation.
Laptop won't boot after crashing	Boot sector damaged	Restore the bootloader using the Windows installation flash drive (command bootrec /fixmbr).
Disk D has become raw (RAW)	Formatting failed	Format the partition to NTFS via Disk Management or Command Prompt (format D: /fs:ntfs).

⚠️ Attention: If, after splitting, files with C:, immediately stop working with the disk and use data recovery programs (Recuva, R-Studio). Do not write new files - this will reduce the chances of recovery!

FAQ: Answers to frequently asked questions

Is it possible to partition a disk on a laptop without losing data?

Yes, if you use the built-in Windows tools (Disk management or DiskPart) or third party programs (AOMEI, MiniTool). However always make a backup important files to an external drive before starting the operation.

How long does it take to partition a disk?

Depends on the type of drive and volume:

• SSD/NVMe: 5-15 minutes (due to high read/write speed).
• HDD: 30 minutes – 2 hours (on disks 1 TB or larger).

If the process takes longer than 3 hours, check your laptop for viruses or abort the operation (but risk losing data).

Is it possible to merge the C: and D: drives back together?

Yes, but for this:

1. Transfer all files from D: to an external drive.
2. Delete the partition D: via "Disk Management" (right button → Delete volume).
3. Expand the section C:by right-clicking on it → Extend volume.

⚠️ All data on D: will be deleted!

Which is better: one partition or two (C: and D:)?

Depends on the tasks:

• One section convenient for beginners and laptops with SSD up to 256 GB.
• Two sections needed if you:
• Store a lot of heavy files (videos, games, projects).
• You often reinstall Windows.
• You use a laptop to work with sensitive data (backups to D: will save you if the system fails).

Why is drive D slower than C: after partitioning?

It's ok if:

• On C: installed SSD, and D: - on HDD (different physical disks).
• Section D: located at the end of the disk (at HDD outer tracks are read slower).
• File system D: — FAT32 (reformat to NTFS).

Solution: Move frequently used files back to C: or optimize the disk (defrag D: /U /V on the command line).