I am trying here because I can't find a solution anywhere.
It is impossible to install Crimson or Catalyst. I get a BSOD "Blue-Screen 0xA5 "Bios not fully ACPI compliant".
I first had this problem as I realised that the driver for the GPU (R9 270X OC Gaming 4G) was "VGA-Standard" and tried to install the drivers. I was able to install some drivers and get the Graphics Card actually detected when I downloaded a version of Catalyst and unpacked it instead of trying to install it. In fact I just has to update manually and browse my computer to select the right .INF-file.
The fact is that I still need Crimson or Catalyst because of the display scaling issue one often has with new AMD/ATI GPUs (and also because I want to understand that problem).
It is a new build. I went through the windows 7 installation with the usual little troubles (USB3, secure boot / UEFI / Windows not updating...) but I had not expected this.It might look like a Motherboard problem, but I don't think so (Windows 7 64bit clean install / Motherboard: Asus Z170i Pro Gaming / Bios flash / CMOS Reset and chipset drivers up to date).
At the beginning I thought about a driver conflict, but now that I could install some and run ddu, it can't be...
What can be the problem with the installation of Crimson here?