@mitu I was just messing around with all of this. I don't have a RP4 yet, but plan to get one. I just wanted to get familiar with the different gaming-centric OSes before I got mine. I'm running this on a laptop that's running Windows 10. I need the ability to have Windows 10 running while I play around with this RP and emu stuff for the time-being. Using VirtualBox gives me that ability. I checked the '3D Acceleration' checkbox and now RetroPie runs. However it's really slow and beyond the configuration menu, I don't see anything else. I've got a VM that only loads an SD card (no 'host' VM OS) of another gaming front-end and the speed of it is great. I'm guessing the slowness has to do with running a system in a system in a VM (or something like that). That's cool. I just wanted to see it.