Are you running Nimez drivers, or just using the registry entries with AMD's drivers? I wasn't able to get AMD Settings to show ReBAR available reliably until I used Nimez per my post above. (I think I did get them to work one time but I can't remember how I did it. It may have been after cross-flashing the GPU BIOS with one from another vendor.) Completely as a side note: Whenever I rendered my system unbootable during testing due to an errant EUFI setting or whatever, I found it very handy to just unplug my RX 470's PCIE power connector and switch the HDMI cable to the IGPU. I didn't have to remove the GPU putting strain on the PCBs to fix my settings.