How to Fix “VT-x is Disabled in the BIOS for All CPU Modes” in Ubuntu VirtualBox

Fix the “VT-x is disabled in the BIOS for all CPU modes Ubuntu VirtualBox” error. Our Virtualizor Support team is ready to assist you.

How to Fix “VT-x is Disabled in the BIOS for All CPU Modes” in Ubuntu VirtualBox

Virtualization plays a vital role in modern computing, allowing users to run multiple operating systems and applications on one machine. However, many users face the “VT-x is disabled in the BIOS for all CPU modes Ubuntu VirtualBox” error when starting a virtual machine. This issue occurs when the system disables hardware virtualization or other software blocks it. Understanding the cause of this error and knowing how to fix it helps ensure smooth and efficient virtual machine performance.

What is a Virtual Machine?

Virtual machine is a software based simulation of a physical computer which functions as an independent computer within a computer. CPU, RAM, and storage are virtual hardware components that altogether create several virtual environments on one machine, businesses and individuals can optimize resource usage and maintain secure, isolated workspaces. This concept is often explained in a Troubleshooting Guide for VirtualBox Error to help new users understand VM behavior.

What is Acceleration technology?

Acceleration technology refers to the methods, tools, and systems designed to enhance speed, efficiency, and performance in business operations, digital transformation, and computing. It aims to optimize performance and productivity by leveraging advanced techniques or tools.

What is Intel VT-x?

Intel VT-x (Virtualization Technology for x86 processors) is a hardware acceleration technology which is designed to improve how virtualization operates at the hardware level. In traditional virtualization, hypervisors rely mostly on software to simulate hardware functions, which can slow down performance. VT-x addresses this limitation by offloading key virtualization tasks directly to the CPU, minimizing overhead and improving execution speed.

Understanding the “VT-x is Disabled in the BIOS” Error

The “VT-x is disabled in the BIOS” error occurs when your computer’s CPU virtualization feature—Intel VT-x—is turned off in the system’s BIOS or UEFI settings. If the error occurs your processor cannot perform virtualization tasks at the hardware level. In some cases, Fixing E_INVALIDARG Error steps can also help clarify misconfigured virtual machine settings related to VT-x.

Mostly VT-x is disabled by default on many computers to maintain compatibility or security. This can be enabled manually through your BIOS or UEFI interface to use virtualization software.

Method 1: Verify Whether Your CPU Supports VT-x or AMD-V

Check whether your hardware supports virtualization or not, if not enabling it in BIOS won’t be possible. This can be done with the help of a lightweight tool called SecurAble. You need to download the official SecurAble page and scroll down to find the Download Now option. Click to download the tool. Open the executable file and when prompted by the User Account Control (UAC), click Yes to allow the program to run. The tool will automatically analyze your processor and display key information about its capabilities. If you see “Yes”, your CPU supports VT-x (for Intel) or AMD-V (for AMD). If it says “No”, your processor doesn’t include virtualization support, and the feature cannot be enabled through BIOS.

Hardware virtualization is supported
Enable virtualization in BIOS or resolving Hyper-V conflicts, to fix the VT-x is Disabled in BIOS error.

Hardware virtualization is not supported
The system cannot run virtual machines that rely on VT-x or AMD-V. In this case, you’ll need to use an alternative system or upgrade to a newer CPU that supports virtualization technology.

Method 2: Enable Virtualization Technology (VT-x) from BIOS

If your system supports virtualization but still shows the “VT-x is Disabled in the BIOS” error, your computer’s BIOS or UEFI settings have likely disabled Virtualization Technology (VT-x). Enable this feature to let your processor run virtual machines efficiently. On some motherboards, also enable Virtualization Technology Directed I/O (VT-d) to ensure full functionality.

Enable VT-x or AMD-V in BIOS

1: Restart your computer. Make sure you repeatedly press the Setup key shown on-screen. You can even search for the keys online for your motherboard model followed by “BIOS key” for confirmation.

2: Move on to the section where virtualization settings are found. The exact location varies by manufacturer, but common paths include navigating through Security and then System Security, Advanced and then CPU Configuration, Advanced BIOS Features, or Advanced and then Intel(R) Virtualization Technology for Intel systems.

3: Enable Virtualization Technology or Intel VT-x. If available, also enable VT-d to support input/output virtualization. Save your changes and exit the BIOS

4: After your computer restarts, attempt to launch your virtual machine again. The error message should no longer appear if virtualization is correctly enabled.

Method 3: Enable or Disable PAE/NX from VirtualBox Manager

If enabling virtualization in BIOS did not resolve the issue, you can try adjusting your PAE/NX settings in Oracle VM VirtualBox.

How to Enable or Disable PAE/NX in VirtualBox
Open Oracle VM VirtualBox and select the virtual machine showing the error. Click the Settings icon in the top toolbar, go to the System section from the left-hand menu, and open the Processor tab. Under Extended Features, check the box labeled Enable PAE/NX, click OK to save your changes, and restart the virtual machine to see if the issue is resolved.

Method 4: Increase or Decrease the RAM Size

Another way to fix the “VT-x is Disabled in the BIOS” error is to adjust the RAM allocated to your virtual machine. Open Oracle VM VirtualBox, select the virtual machine causing the problem, and click the Settings icon. In the Settings window, go to System and open the Motherboard tab. Move the Base Memory slider to increase the allocated RAM, then click OK to save your changes and start the virtual machine. If the error persists, return to the Motherboard tab, reduce the RAM allocation below the previous value, and restart the virtual machine to check if this resolves the issue.

Method 5: Prevent Third-Party Antivirus from Interfering with Hardware Virtualization

The “VT-x is Disabled in the BIOS” error can also be caused by the interference from third-party antivirus software. Programs like Avast and other security tools often include background services or sandboxing features that utilize hardware virtualization, which can block VirtualBox or similar applications from accessing those resources.

If you’re using Avast, open the antivirus dashboard, navigate to the Settings and then Troubleshooting, and uncheck the option labeled Enable hardware-assisted virtualization. After making this change, restart your system to apply the settings.

For users of other antivirus programs, look for a similar setting related to virtualization or sandboxing and disable it. However, note that some antivirus clients do not allow full control over these features, in which case you may need to temporarily uninstall the software or switch to a different security solution to test whether it resolves the issue.

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Conclusion 

Fix the “VT-x is disabled in the BIOS” error for all CPU modes in Ubuntu VirtualBox to ensure smooth virtualization and stable system performance. Enable VT-x in the BIOS, adjust VirtualBox settings, and prevent antivirus interference to quickly restore proper virtualization and run Ubuntu efficiently.

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