I think i found the answer. Windows counts the total speed including the effective bandwidth, while most Linux utilities only report the raw clock speed.
I did this and i can tweak the voltage and stuff. Just max memory is wrong. On amd adrenalin i was running vram 2124mhz and here only 1075mhz. And how does the voltage work in CoreCTRL i only know how to do it in amd app in mv but i dont know what -30 is.