Hi, everyone. I was doing some power consumption testing on my Framework (11th-gen i7, batch 4) which led me to discover a rather odd behavior. On my laptop, the top left expansion port consumes more power both when charging the laptop through it or when having any expansion module attached to it (including the USB-A modules, but excluding the USB-C passthrough modules, of course).
Using the same power adapter and USB-C power meter on each port, I got the following readings for idle power consumption during S3 sleep (charger on referenced port, all other ports empty):
Top Left: 1.55 W
Bot Left: 1.22 W
Top Right: 1.22 W
Bot Right: 1.22 W
I also tested with the HDMI expansion card and the USB-A expansion card in all of the different slot configurations, and having either card in the top-left slot caused a similar difference in overall system power consumption compared to the same module being in a different slot.
But here’s where it gets even weirder. My friend also has a Framework (11th gen i7, newer batch than mine), so I did the same tests on his. For his machine, there were also ports that exhibited a higher idle load, but it was the bottom-left and bottom right ports. Here are the measurements for his (charger on referenced port, all other ports empty):
Top Left: 1.07 W
Bot Left: 1.42 W
Top Right: 1.09 W
Bot Right: 1.45 W
Both laptops are running BIOS v3.07. Mine was upgraded to it, while his came from the factory with it installed.
Can anyone else corroborate these findings? And can anyone from Framework comment on why this might be the case? I’m more than happy to do any additional tests or experiments, or to test any beta firmware / BIOS updates.