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Comment by linuxhansl | Hacker News Reader

Hmm... I have the model with the NVidia GPU. By default I have it turned off (using no extra power) and I have a simple script that I use to turn it on when I want to.

ThinkFan works well to control the fans too.

Lastly I found that the SD card reader prevented the CPU package from entering C10.

With all that I find that in idle mode my laptop (X1E Gen2, almost identical to P1 Gen2) consumes 3.9w, which is pretty good. The fan only turns on when I compile something large or do something with the NVidia card.

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Can you share your script for toggling the video card?

No elaborate script is needed these days, the kernel's runtime power management suspends the card automatically as long as /sys/bus/pci/devices/…/power/control is "auto" and the device isn't being used (the nvidia/nouveau module is unloaded).

Documentation for the nvidia module claims [0] runtime pm is supported even when the module _is_ loaded for GPUs since Turing, but I haven't been able to test that (mine is older than that).

[0] https://download.nvidia.com/XFree86/Linux-x86_64/435.17/READ...

That. I used to use bumblebee, but with recent NVidia drivers it's automatic.

That said, if I want to start a process with using the NVidia driver and card I use this script.

  #!/bin/bash
  __NV_PRIME_RENDER_OFFLOAD=1 \
  __GLX_VENDOR_LIBRARY_NAME=nvidia \
  __VK_LAYER_NV_optimus=NVIDIA_only \
  exec "$@"

> consumes 3.9w

is this figure taken from software (powertop) or from a wall power-meter (i.e. including the psu)?

It's measured from the battery when unplugged: /sys/class/power_supply/BAT0/power_now

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