Asus UX501VW discrete card is still ON after attempt to power off

[larixer]

Hi,

I'm trying to use bbswitch for power saving on Asus UX501VW.
After attempt to power off discrete card with bbswitch it is reported to still stay powered ON.

$ echo OFF > /proc/acpi/bbswitch
$ cat /proc/acpi/bbswitch
0000:01:00.0 ON

Linux kernel version: 4.8.2-040802-generic
XOrg: 1.18.4
xorg-xserver-video-intel: 2.99.917
Distribution: Ubuntu 16.04 LTS

Nouveau or proprietary NVidia drivers are not loaded

All the info as requested by README for issuing bug report is attached to this post.

Thank you for great module!

acpi_dump_info.txt
ASUSTeK_COMPUTER_INC.-N501VW.tar.gz
dmesg_bbswitch.txt
versions.txt

[Lekensteyn]

If you just want to save power, I recommend you to remove bbswitch (since you do not use bumblebee). The nouveau kernel module in kernel 4.8 supports a newer PM method which is superior to the current method in bbswitch (for newer laptops).

Can you give that a go? I have some notes at Bumblebee-Project/Bumblebee#808 (comment)

[larixer]

Thank you for quick reply!

I have tried to follow your notes. It wasn't very straightforward on Ubuntu, but I've managed to load nouveau and at the same time use intel modesetting driver for X. I assume I should use vgaswitcheroo to turn off NVidia card?

I have the following with vgaswitcheroo:

After boot:
# cat /sys/kernel/debug/vgaswitcheroo/switch 
0:IGD:+:Pwr:0000:00:02.0
1:DIS: :DynOff:0000:01:00.0
# echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
# cat /sys/kernel/debug/vgaswitcheroo/switch 
0:IGD:+:Pwr:0000:00:02.0
1:DIS: :DynOff:0000:01:00.0

If I understand correct, DynOff on Nvidia card means it's not fully powered off, right?
Full dmesg.txt is attached as well as output from xrandr.

Thanks a lot!
dmesg.txt
xrandr.txt

[Lekensteyn]

vgaswitcheroo should not be used for ON/OFF, as you can see the nvidia device (01:00.0) is listed as DynOff which shows that nouveau manages the power using the runtime power management framework (and indeed, it is currently off).

So you do not have to do anything else now, it seems working now with proper power savings. If you want to use an external monitor later, then you might have to run lspci or xrandr to trigger power-on, but otherwise everything is automatic.

[larixer]

I see. Thank you for your help!

[Lekensteyn]

You're welcome!