Alienware Steam Machine not shutting down properly

Hi,

I bought the Alienware Steam Machine, because the Alienware Alpha wasn’t available in my country at that time. Because I want to play my Windows-only games I first installed Windows 10 on the Alienware Steam Machine (I’ve researched, that the Steam Machine and Alpha are equivalent in terms of the hardware here). Then I noticed, that the Steam Machine won’t shut down properly, so I started researching. I found, that this would be a common issue with Windows 10 because of the hibernate feature or some bugs with the intel management drivers. None of the solutions online helped me. So I decided to install a clean version of Windows 7. I thought the problem was solved but unfortunately it was not. 

The concrete problem is the following: When I shut down the Steam Machine everything seems normal (no display output, the illumination of the usb keyboard turns off etc.) but the system fans and the alien-light is still on. I updated every possible driver, windows and the bios via the dell software. 

Do you have any suggestions? Thank you so much!

Edit: PS: Everything else is working really well on both win 10 and win 7