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Comment by speakspokespok

6 days ago

There is literally no way. Spill the beans!

Sorry, thought I had posted, but didn't get through. It's a T480 with the 72Wh and the 24Wh battery running on FreeBSD. Screen has also been replaced with a low power usage screen which helps a lot in saving battery while still giving good brightness.

Most of the time I am running StumpWM with Emacs on one workspace and Nyxt in another. So just browsing and coding mostly.

OpenBSD gets close, but FreeBSD got a slight edge battery wise. To be fair, that is on an old CPU that still has homogenous cores. More modern CPUs can probably benefit from a more heterogenous scheduler.

Probably has the extra big battery. Thinkpads have options for different sized batteries.

  • Or they just got one of the 'good' models and tuned linux a bit. I have a couple lenovo's and its hit/miss, but my 'good' machine has an AMD which after a bit of tuning idles with the screen on at 2-3W, and with light editing/browsing/etc is about 5W. With the 72Wh battery that is >14h, maybe over 20 if I was just reading documentation. Of course its only 4-5 if i'm running a lot of heavy compile/VMs unless I throttle them, in which case its easy over 8h.

    One of my 'bad' machines is more like 10-100W and i'm lucky to get two hours.

    Smaller efficient CPU + low power sleep + not a lot of background activity + big battery = very long run times.

    • !!! I can get my laptop to 7.5W under web browsing with powertop tuning, but not 5. What did you do?