Endless rebooting loop after upgrading to windows 10 on Alienware 17 R2

I have a new alienware 17 R2 and after successfully upgrading the windows 10, it goes into an endless  reboot at the alienware logo/spinning circle screen and so never gets to load windows.  I've had boot onto a windows recovery usb to roll back to 8.1 to be able to use it.  Any help would be much appreciated.