https://bugs.freedesktop.org/show_bug.cgi?id=109887
--- Comment #5 from bednarczyk.pawel@outlook.com --- Did you manage to get this resolved. I have the same issue and in my case setting P6 = P7 Frequency, the memory clock gets stuck at P0 167 Mhz. I tried 5.1 RC-3 but no joy either.