https://bugzilla.kernel.org/show_bug.cgi?id=206351
--- Comment #1 from Matt McDonald (gardotd426@gmail.com) --- Actually, the new vBIOS memory clock should be 1750MHz, not 1500. Either way it's far to low on Linux, and this was not an issue with the Polaris cards, they correctly set memory frequencies in line with the vBIOS.