I have been searching for information on the topic for a while now and haven’t found anything useful so I’m creating a post here for help.
I’m trying to understand how the battery/different chargers interact with system performance on the Framework 16 with the 7840HS + 7700S dGPU.
I have been using the UPower cli tool to monitor energy flowing to and from the battery, and using an ac outlet power meter to monitor energy flowing to the charger from the wall.
I have tested performance in a game in 3 different power configurations and I don’t understand the outcome. While monitoring battery power flow with the command watch -n 30 upower -i /org/freedesktop/UPower/devices/battery_BAT1 and the charger connected to the hardware power meter I see the following results.
On battery:
0 W from wall
84 W discharging from battery
34 fps in game.
On 100 W charger (Nekteck 100W USB C Charger PD 3.0):
100 W from wall
15 W discharging from battery
56 fps in game.
On Framework 180W charger:
180 W from wall
4 W charging to battery
96 fps.
All these tests occurred with the battery ~80% charged and OS set to balanced power profile (I saw no difference in performance/power usage between balanced & performance profiles during these tests)
It seems the system can use more power to get better performance up to at least 180 W, and the battery is capable of outputting at least 84W
My question is; why doesn’t the battery output 84 W when I plug in the 100 W charger giving me presumably the same performance as the Framework 180 W charger? Why does it only draw 115 W combined? What is the maximum input/output rate of the battery? If I’m misunderstanding something I would love to be informed on the subject.