openminded

hi, I have a Dell Precision 5550 with i7-10850H and Nvidia T2000. Specs are similar to the XPS 15 9500 model discussed here. I cannot find any EFI that boots, including those posted for the XPS 9500. I have the 1.19 BIOS installed. Does anyone have an EFI that should boot ? @djuby I was suspecting the USB part of things, what USB-c port are you using and which dongle and type of stick? I am trying a Big Sur installer now with the last EFI posted and it seems all goes well but the UI does not start. Last thing in log is : AppleActuatorDeviceUserClient::start entered and the nothing. Any help is greatly appreciated!