If you mean "over_voltage=-2" That seems to be working now. Can you clarify that? Were there any recent fixes? I tried that yesterday with everything up to date. Both -1 and -2 values resulted in ~1.1V supply voltage (looks like a maximum voltage the regulator can output). Needless to say, temperat...

jamesh, Thank you for the info. This would be consistent with what I am seeing - lowering idle cpu frequencies has almost no impact on power consumption but changing (increasing) supply voltage increases power consumption dramatically. I will wait for the updated vli firmware, any eta would be great...

It is the newest version of Raspbian. Installed from image 2 days ago, an upgrade produced no meaningful changes. I've lowered arm_freq_min and core_freq_min so the idling frequencies are lower (without reducing the supply voltage) - strangely, there is no difference to the temperatures, or a very m...

Nope, values in the range of [-16,-1] result in supply voltage of ~1.1V. Positive values (I tried only "1") work as expected. Looks like this config value has changed in RPi4.

How to undervolt the SoC and reduce clock frequencies?

With the case cover on and usb3 memory stick plugged in, it idles at >75C. Any activity pushes the temperature over 80C and the SoC starts throttling, which is very noticeable, e.g. when scrolling a page in a web browser. Without the case cover and usb3 stick, idle temperatures are around 10C lower,...