The one BIOS tweak you need to boost VirtualBox speed

Are you running Windows 10 or Linux in VirtualBox? Are you running Windows 8, 7, Vista or XP in a virtual machine? One simple tweak can massively increase the performance.

VirtualBox is a great way to run other operating systems on your computer. You can run any version of Windows, from XP all the way up to Windows 10. It is perfect for running old software that is not compatible with the current version of Windows on your computer, and it is brilliant for testing new versions of Windows that you want to try out. It is a great way to run Linux distros too.

Run Windows 10 in VirtualBox

Windows 10 running in a window in Windows 8

What makes VirtualBox so good is that you can run any operating system you want in a virtual machine. It is a bit like an emulator of a retro computer like an Atari, Commodore, Gameboy, Sinclair and others. The operating system runs in a window on the desktop and so it does not affect your current Windows setup.

Running one OS inside another OS requires a fair bit of memory and processing power, and it is best if you have plenty of each. Modern processors have multiple cores and there can be up to four. Each of these cores can be two virtual cores, so you can have up to eight virtual processor cores in the computer, depending on the model of CPU you have.

Many Intel Core i7 processors, for example, have four cores and eight virtual cores. A very useful feature of VirtualBox is the ability to choose the number of cores and this means you could have two cores running the OS in VirtualBox, leaving six cores running the OS on the computer. This way the computer still manages to run quite speedily even though you are running another OS inside it. You can also run 32-bit or 64-bit operating systems if you have 64-bit Windows.

VirtualBox running Windows 7

Run other operating systems in VirtualBox

The problem I had was that VirtualBox would not allow more than one CPU core to be assigned to an operating system. In addition to this, VirtualBox would not run 64-bit operating systems. An error message stating that virtualization was not supported was displayed whenever this was tried.

If you have Hardware Virtualization VT-x/AMD-v for Virtualbox error messages, the problem could be solved with a simple BIOS tweak, allowing VirtualBox to run guest operating systems at full speed.

Switch on the computer or restart Windows and just before Windows starts to load, press the hotkey to enter the BIOS setup utility. This varies from computer to computer and on my HP laptop it is F10. Other computers may use F1, or F2. Try them all.

The BIOS setup utility is navigated using the left/right, up/down arrow keys and Enter. Pressing right arrow goes to the System Configuration section on my computer and there is a setting labelled Virtualization Technology. It was disabled on my computer and it seems that this is the default for my HP laptop. This limits operating systems in VirtualBox to 32-bit and one CPU core.

Virtualization settings in the BIOS

Virtualization settings in the BIOS on an HP laptop

 Select Virtualization Technology and press Enter to enable it. There is usually a menu at the bottom of the screen and on mine you press F10 to save and exit. There is also an Exit menu at the top.

Let the computer boot up as normal and then you can start VirtualBox and use 64-bit operating systems and assign multiple cores to it.

notepad Save 50% on RAWinfopages online courses! Get 50 Shares A Day - PDF with 50 places to promote your blog/website daily!
Join our FREE newsletter!


This setting works exactly the same with the VMware player too, which is an alternative to VirtualBox. Solve your VMware virtualization error with the same BIOS tweak.