plug 1 480 into x16 slot, boot into w10 using igpu, check to see if the 480, or unidentified device/generic video adapter is in device manager
Tried this it knows there is a gpu ,but says it's a general vga gpu or somthing, the miner doesn't recognise it nor does windows or msi afterburner.
Does amd driver installer detect it? DDU all your drivers and run the installer, if it gives you an option to install the driver at all then it means it does, and proceed with reinstallation (can try a dif version as well--try 16.7)
if that doesnt work, run the amd installer once so it extracts driver files to the specified destination (generally program files/amd or program files(x86)/amd), then use device manager to manually search for drivers in the aforementioned directories (try both--just select the directory, it will automatically search it)