So I currently have digital license from windows 7 to windows 10 upgrade. Installation is in CSM Boot mode right now. Will windows automatically activate if I reinstall windows in UEFI mode when I connect to the internet like it does now that is in CSM boot mode? What advantages does UEFI bring for a laptop? Faster boot time? What else? Also how do I know that I am booting my installation from usb in UEFI mode? Quick search on the web: - set in bios setup UEFI mode and secure boot - Prepare the usb device in Rufus. Select GPT for UEFI only. Select FAT32. UEFI specs define FAT32 as mandatory. Is that all or I am missing something?