Why do I have drastic loss of battery life on upgrade from 15.10 to 16.04?

Question

I have a dell xps15 9530 with high capacity battery. On Ubuntu 15.10 I was getting 6-8hrs battery life using intel graphics, but on 16.10 I only get around 2 hours. Powertop shows 20-30w power usage while idle.

Is there any way to find what is causing this?

Just for anyone with a similar issue, I switched to vanilla Ubuntu and the problem was gone. The issue occurs on Ubuntu-Gnome. I switch back to the Ubuntu-Gnome partition every few months and apt-get update, but the problem is still there. — mp035, Apr 21 '17 at 03:14

score 1 · Accepted Answer · answered Apr 21 '17 at 03:30

1

Ok, so after nearly 12 months, I have solved it. The problem was the NFC radio on the dell xps was permanently enabled. In vanilla Ubuntu there does not seem to be a driver, but there is one in Ubuntu Gnome.

Running

rfkill block nfc

reduced the power consumption by around 8 watts on standby.

answered Apr 21 '17 at 03:30

mp035

151
6

Ubuntu GNOME and Unity come with exactly the same kernels and drivers. However, GNOME may enable Bluetooth by default while Unity doesn't. – David Foerster Apr 21 '17 at 09:54

Why do I have drastic loss of battery life on upgrade from 15.10 to 16.04?

1 Answers1