Fix Slow Performance of Windows 10 Guest in VirtualBox

Virtualbox Icon Big

VirtualBox is my virtualization software of choice. It is free and feature-rich, so all my virtual machines are created in VirtualBox. Starting with Windows 10 April 2018 Update (and its pre-release versions), I noticed very poor performance of Windows 10 guests in VirtualBox. Here is how I fixed it.

Let's start with official Windows 10 system requirements, which are as follows.

Processor: 1 gigahertz (GHz) or faster processor or SoC
RAM: 1 gigabyte (GB) for 32-bit or 2 GB for 64-bit
Hard disk space: 16 GB for 32-bit OS 20 GB for 64-bit OS
Graphics card: DirectX 9 or later with WDDM 1.0 driver
Display: 800x600

Now, let's create a new Windows 10 machine in VirtualBox and see which settings it will use by default.

Click on the File - > New Machine to open the new machine wizard.

Select Windows 10 (32-bit or 64-bit) and fill in the machine name box.

By default, VirtualBox will dedicate 1 GB of RAM for a 32-bit Windows 10 machine, and 2 GB for its 64-bit version. In my case, it is a 64-bit instance.

The virtual hard drive will get 50 GB of disk space.

It is OK to use VDI as the hard drive image format. I am using a dynamically expanding virtual disk to save space on my real hard drive. However, using a pre-allocated (fixed size) disk image will speed up your guest OS a little.

Your virtual machine is now created. It fits the official system requirements, so everything should be fine.

However, after installing Windows 10 on such a virtual machine, you will face extremely poor performance in the guest OS. It will work slow as hell, making you wait for several minutes for simple action such as opening Settings or File Explorer.

Fix Slow Performance of Windows 10 Guest in VirtualBox

The secret is in the CPU configuration of the virtual machine. By default, it is set to single core.

While the official system requirements don't mention CPU cores, it looks like Windows 10 needs at least a dual-core CPU to run smoothly. I recommend you to change the Processor parameter to half of your CPU cores. i.e. if your CPU is 8-core, set this parameter to 4.

Also, increasing RAM to 3 GB (3072 MB) allows the OS to work better. It is not really necessary, but it's better to make this change if you have enough memory on the host hardware.

Now, start your Windows 10 virtual machine. You'll notice the difference.

Support us

Winaero greatly relies on your support. You can help the site keep bringing you interesting and useful content and software by using these options:

If you like this article, please share it using the buttons below. It won't take a lot from you, but it will help us grow. Thanks for your support!

Author: Sergey Tkachenko

Sergey Tkachenko is a software developer who started Winaero back in 2011. On this blog, Sergey is writing about everything connected to Microsoft, Windows and popular software. Follow him on Telegram, Twitter, and YouTube.

13 thoughts on “Fix Slow Performance of Windows 10 Guest in VirtualBox”

  1. If you are using Hyper-V in Windows to set up a virtual machine you also need to change the CPU to more than one core before you start your installation.

      1. Really? Fluent Design transparency or reveal effects have never worked for me in VirtualBox. Even with the VirtualBox extensions installed. Is there some setting I’m not aware of? I’ve been reading about this over at VirtualBox forums a while back and the consensus was that it doesn’t work because VirtualBox graphics drivers don’t support it.

        1. Sorry, I was wrong.
          I have managed to get the Fluent Design effects over rdesktop in Linux, but not in VirtualBox.
          You are right, the driver doesn’t provide acceleration.

  2. For me, these option were not sufficient !
    Test with HDTUNE : HD (SSD) performance = ~8GB/s. Ridiculous.
    and very poor usage of HDD
    I tried a lot of things, and finally replace CHIPSET PIX3 by ICH9
    And HDTUNE displays now about 32 GB/s
    Not very high for SSD disk, but globally, speed of my virtual machine becomes now 4 times greater.
    Much more acceptable !!!

    1. Thanks – changing the chipset from PIX3 to ICH9 also worked for me.
      My Win10 guest is now nice and quick. Before it was like it was trying to swim in porridge.

  3. I think I have finally found the answer. My Virtual box was perfect for some years and then suddenly started to hang badly, to a point it hardly worked. I have used every single option in various forums to get it working, to no avail. Just by chance I noticed by Avast software in the virtual box was also very slow loading, so decided to uninstall it. Immediately the virtual box started running again and is now back to normal. So give it a try and uninstall your virus software and see what happens.

  4. I spent weeks trying to figure this all out. I tried every tip that I could find – messing with virtualbox settings, windows settings, etc. I actually solved my problem on accident. I noticed that on top of my windows 10 being sluggish its network times were also slow over a bridged network. In the settings for Windows 10 network there is an “advanced” area. I changed the setting from “Intel desktop” to “Intel Server” and it was like the fog had drifted away. Not only was my network speed much better the entire desktop was snappy. YMMV – my host is an enterprise-level box.

  5. Thanks to the author and to those within the comments section, doing a combination seems to have helped speed my VM up a bit!

  6. run “msinfo32.exe” to see if “Virtualization-base security” is enabled.

    it must be disabled.

    tool dgreadiness v3.6 is for this.

    usage: “./DG_Readiness_Tool_v3.6.ps1 -Disable -AutoReboot”

Leave a Reply

Your email address will not be published.

Exit mobile version
Using Telegram? Subscribe to the blog channel!
Hello. Add your message here.