[ubuntu] 16.04 won't shutdown on MSI laptop

On an MSI GS60 2QE (Ghost Pro) every time I try to power off the laptop, it just freezes.
I disabled the quiet splash on grub config so I could see what was going on and it gets to "Reached target Final Step. Starting Power-Off... reboot: Power down" and then freezes completely (please see the attached)
I have tried the Alt + Sys Rq combination and nothing happens either.

I have tried the following configurations:

• acpi=off --> won't even boot
• noapic --> fixes the issue, but keyboard doesn't work at all
• nolapic --> no difference
• apm=power_off --> no difference
• reboot=bios,force,efi,warm, etc...
• irqpoll --> no difference
• acpi=force --> no difference
• xhci quirks on grub config didn't help either

I have also tried to do a swapoff before shutting down, to no avail.

Strangely enough, reboot works just fine

I have tried on Keel 4.4.0-22-generic and 4.4.0-21-generic, no difference here. On a fresh USB-booted install the issue is also present so I believe it has nothing to do with installed software.

Happens with the Nvidia driver and with Nouveau as well (it even happens on a fresh install as I mentioned).

Any help is very appreciated