What happens when you remove the hard drive from a computer?

Removing the hard drive from a computer can have several consequences, depending on the type of computer and setup. Generally speaking, removing the hard drive will prevent the computer from being able to boot up into an operating system, access installed programs and data stored on the drive.

Why Remove a Hard Drive?

There are a few main reasons why someone may want to remove a hard drive from a computer:

  • To replace it with a larger/faster hard drive
  • To access data on the drive from another computer (data recovery)
  • To securely wipe or destroy the data on the drive
  • To troubleshoot hardware issues and test components

When removing a hard drive, it’s important to first back up any data on it that you want to keep. Once removed, the computer will no longer be able to access the operating system or data that was stored on that hard drive.

Computer Won’t Boot

One of the most immediate effects of removing the hard drive from a computer is that the computer will no longer be able to complete the boot process and load the operating system. This is because the operating system files, such as Windows, Linux, or macOS, reside on the hard drive.

Without the hard drive, the computer will turn on but get stuck on a black screen or display an error message saying no boot device is found. This is because the BIOS or UEFI firmware that handles the machine’s boot process no longer has access to the files it needs to load and launch the operating system.

Some computers may be able to boot into the BIOS settings without a hard drive, but they won’t be able to proceed beyond that point to load the operating system. The boot process is halted because critical system files cannot be accessed.

Operating System Becomes Inaccessible

As mentioned above, removing the hard drive causes the operating system files to become inaccessible. Windows, Linux, macOS, and other operating systems are installed to specific folders on the hard drive.

Without the hard drive present, the computer loses the ability to access the critical system folders and files it needs to load the graphical interface, apps, services, settings, and overall environment. The operating system essentially becomes non-functional.

Loss of Programs and Applications

In addition to the operating system, programs and applications are also installed to the hard drive. This includes things like web browsers, productivity suites, creative software, games, utilities, and more.

With the primary hard drive removed, the computer loses the ability to locate and open any of the programs installed on that drive. This can include both pre-installed software that came with the computer, as well as apps manually installed later on.

Unless the programs are installed on a secondary internal drive or external drive that is still connected, the computer will not have access to its software if the primary hard drive is taken out.

Loss of Personal Files and Documents

One of the biggest risks of removing the hard drive from a computer is losing access to personal files. This includes documents, photos, videos, music, downloads, and any other data stored in the user’s folders.

On Windows computers, this typically includes folders like Documents, Pictures, Music, Videos, and more. On Macs, it includes folders like Documents, Music, Movies, and Photos. Linux systems have similar default folders for user files.

With the hard drive removed, the connection to these folders is lost. Unless files are saved elsewhere off the hard drive, they will become inaccessible to the user if the hard drive is taken out.

Hardware Changes and Detection Issues

Removing the hard drive can also create issues with hardware detection and installed components like RAM, the CPU, and GPU.

This is because the computer’s BIOS/UEFI firmware may rely on the hard drive to store data and settings related to installed hardware. For example, on many PCs, the BIOS keeps a record of RAM timings, CPU specs, and other details that help optimize performance.

With the hard drive missing, some computers may fail to detect hardware properly on boot up. This can result in the machine needing to be reconfigured after replacing the hard drive.

Securely Erasing Data

While the effects above are all related to normal computer operation and maintenance, another purpose for removing a hard drive is to securely erase its contents.

If the hard drive contains sensitive files or confidential data that needs to be permanently destroyed, removing it from the computer allows connecting it to another device designed specifically for secure data wiping.

There are special machines that can interface with hard drives and overwrite data beyond recovery. This ensures no files can ever be read again after the process is complete.

Troubleshooting and Testing

Computer technicians will also remove hard drives as part of troubleshooting efforts, or to test components individually.

For example, if a computer is having boot issues or displaying a potential hard drive failure, removing the drive allows it to be examined closely or connected to a different machine for analysis.

Testing boot process, RAM, and other components separately from the hard drive is also helpful in pinpointing an issue when diagnosing computer problems.

Replacing or Upgrading the Hard Drive

Finally, the main purpose of removing a hard drive for most users is to replace it with a new one. Reasons may include:

  • Installing a higher capacity hard drive
  • Upgrading to a faster solid state drive (SSD)
  • Replacing a failed or damaged drive

After removing the old hard drive, a new one can be installed in its place and the operating system can be reinstalled or restored from a backup.


In summary, removing the hard drive prevents the computer from being able to boot into the operating system and access installed software, personal files, and settings. The computer will turn on, but only gets as far accessing the BIOS or UEFI firmware.

While this can be disruptive if the hard drive is removed unintentionally or replaced improperly, there are practical reasons for intentionally removing a hard drive like securely erasing data, troubleshooting hardware, or upgrading to a new drive.

As long as data is backed up and proper precautions are taken, removing a hard drive can be a necessary part of computer maintenance and upgrades.