Nice; my experimentation was actually before this (and I posted it to the RPi forums), the firmware updates _did_ make a measurable difference but I decommissioned the setup shortly after testing it.

EDIT: What that post is missing, is a comparison of all generations of the Pi; We know the Pi4 is hot, but I haev every previous generation sitting in the drawer, might be interesting (for me at least) to do some comparison.

My RPI4 sits in a closet. 67 max temp, usually 57. I got the heatsink-enclosure. And I haven't myself made the firmware update - I may still have the bad one.