Open Task Manager (Ctrl+ALT+DEL) and click on the Tab "Performance" then on "Memory".
That will show at what speed your RAM is actually running at like mine:
My RAM's native speed is 3600Mhz but without using XMP it reverts to the Motherboard's SPD Speed which is 1xxxMhz.
If Windows Task Manager shows the correct Memory Speed then ignore AMD Radeon Memory Speed. It might just be reading the RAM's SPD Speed and not the XMP speed.
If Task Manager is showing the SPD Speed you can enter BIOS and use XMP Profile to make it run at its native speed.