I have it! Legion5slim 16aph8 with 4070. The crucial option is to set NVreg_DynamicPowerManagementVideoMemoryThreshold=0. The driver 555.52.04, X11, my full working parameters are:
options nvidia NVreg_DynamicPowerManagementVideoMemoryThreshold=0
options nvidia “NVreg_DynamicPowerManagement=0x02”
options nvidia-drm modeset=1
blacklist nouveau
blacklist nvidiafb
blacklist rivafb