The problem: Windows 10 works slowly on Virtualbox virtual machine, while Windows 7 is fast and snappy. You may see similar situations on the Internet forums. People often ask “Why is my Windows 10 so slow on virtualbox VM? I have Core i7, 16 GB of RAM, I assigned 4 cores of CPU and 4 GB of RAM to the virtual machine but the CPU usage is 100% all the time! Svchost.exe process is loading CPU to 100%” Let us see what are the possible reasons of low performance and how to speed up Windows 10 on virtual machine.