This is my laptop: HP 250 G1 My laptop came with Windows 8 x64 OEM Pre-Installed. Key integrated inside BIOS. A while ago, I downgraded to Windows 7 x64 with a fresh install from USB key with UEFI disabled and using Legacy mode in BIOS settings. I did not make an image/recovery image before doing so. And I activated with Windows 7 Loader by Daz. (Did this override the Win8 pre-installed key in my BIOS?) Now I want to go back to Windows 8. I'm willing to do a clean install. The image I have for Win8 is "en_windows_8_x64_dvd_915440.iso". Do I just have to uninstall Windows 7 Loader by Daz (hoping this will revert the Win7 Loader by Daz key back to pre-installed one?), then mount the Win8 .iso on a USB key, enable UEFI in BIOS, and reinstall Win8, and it will use the OEM key inside the BIOS the laptop came with?