Verifique este para ver qual é o seu problema. E verifique novamente sua configuração de inicialização do usb (talvez o USB seja escolhido para instalar o MBR):
I was able to solve the issue. I founnd that the issue was due to the fact that I did not choose "GPT" when creating the USB drive with Rufus. It was always selected as MBR. Once I selected the partition scheme correctly the installation completed and the computer did boot without the USB connected.