I have the same problem, and it only occurs when there's an onboard Intel Graphics card present in the system. After some investigation i figured out the the Intel drivers are the problem. When hardware is getting probed for detection, and the intel graphics is found it then asks for a driver. The hardware it is actually looking for is the second (non present) monitor. This is for dual display configuration. So i seems the intel drivers are the cause. The setup continues as normal, check HDD activity during the display of the found new hardware box, and you'll notice hardware detection continues in the background. It's mainly an annoying thing, everything works normally after setup completes. But if there is someone who knows how to disable the new hardware found box during setup.. i'd like to know.