ulMaxSystemMemoryClock 3205 drivers/gpu/drm/amd/include/atombios.h   ULONG                           ulMaxSystemMemoryClock;       //in 10kHz unit
ulMaxSystemMemoryClock 2752 drivers/gpu/drm/radeon/atombios.h   ULONG	                          ulMaxSystemMemoryClock;	    //in 10kHz unit