Hello everyone !
I have no idea if I’m in the right community, because it’s a mix of hardware and some light code/command to extract the power consumption out of my old laptop. I need some assistance and if someone way more intelligent than me could check the code and give feedback :)
Important infos
- 12 year old ASUS N76 laptop
- Bare bone server running Debian 12
- No battery (died long time ago)
- Running a dozens docker containers.
Because I have no battery connected to my laptop I’m unable to use tools like lm-sensors, powerstat, powertop. But from the following ressource I can estimate the power based on the Energy.
time=1
declare T0=($(sudo cat /sys/class/powercap/*/energy_uj)); sleep $time; declare T1=($(sudo cat /sys/class/powercap/*/energy_uj))
for i in "${!T0[@]}"; do echo - | awk "{printf \"%.1f W\", $((${T1[i]}-${T0[i]})) / $time / 1e6 }" ; done
While It effectively outputs something, I’m not sure if I can rely on that to estimate the power consumption.
Thanks :).
If you’re not running with a battery, the maximum wattage of the charging brick should be shown on the brick itself. Either that or you can calculate it with P=I*V (amps * volts). That won’t give you what the laptop draws on average (likely much less than the calculated value) but it will give you a maximum.
It will give you the maximum of what the power supply is capable of providing which is nothing like what the laptop actually uses.
all the laptops I’ve ever had have been able to reliability pull the full power (like within 30 watts) of their power adapter rating so that’s a good estimate
I’m not sure about that. Specially because it’s used as a bare bone server without any GUI with the lid closed. So it will draw way less power than showed on the charging brick.
ah I misunderstood, thought you talking about underload, not idle power use