Ryzen 7 1700 refusing to install Windows 7

ethanril12 · March 30, 2019

So, I've had my Dell Inspiron 5675 for about two years now. I've gotten tired of Windows 10, though, and with Windows 7's sell by date right around the corner, I decided to give it a run for its last 10 months or so. However, when I attempt to run the installer from a DVD, it shows me the error:

The BIOS in this system is not fully ACPI compliant. Please contact your system vendor for an updated BIOS version.

Along with the error code 0x000000A5.

I've taken all the usual precautions; using a PS/2 keyboard, unplugging all USB devices, making sure all the settings in my BIOS setup are correct, but seemingly nothing works, although I know its possible because many others have gotten their AMD Ryzen computers to not only install, but run Windows 7 perfectly.

So my question is, should I just leave it alone and run with Windows 10, or is there some way that I can get my BIOS updated or fixed to work with Win7?

GoodBytes · March 30, 2019

Windows 7 does not fully support UEFI.

You need to tell your UEFI to emulate the old BIOS, if you can.

Delicieuxz · March 30, 2019

There are two installers on the DVD. One if the UEFI version, and the other is the legacy version. When choosing to load the installer with the F8 key or whatever while starting up, make sure that you select the installer version that matches your BIOS (either UEFI or legacy / non-UEFI).

If you've done that and you're loading the UEFI version with your BIOS being set to the UEFI version and it still just doesn't work, then sets your BIOS to legacy mode and load the legacy / non-UEFI version of the Windows 7 installer.