I have: AMD Ryzen 5 3400G with Radeon Vega Graphics and I don't know if this is the problem with Graphic integrated CPU or Virtualbox-6.1.16-r1
I run Windows 7 in Virtualbox and browsing file manager files in Windows is very slow. Sometime I click on a file and have to wait second or two before file is highlighted. Gentoo is running normally and respond normally. I run same Windows 7 in Virtualbox on: AMD Ryzen 7 3800XT 8-Core Processor and browsing file is more responsive.