[SOLVED] Excessive battery consumption

[Metal Mick]

HI,

I have an Alienware 17 R3, with an i7 and 970M chip. It is fitted with Killer wifi and LAN connection. I have a 128 GB Samsung SSD for Windows (which it came with) and I have a separate 256 GB SSD for Linux; I also keep data on a third SSD (an Evo 850, from memory).

A while ago, I installed Mint 17.3 and had to go through some gymnastics to get the LAN and wifi working, which I didn't mind and all works very well.

Despite a huge battery, I'm getting around 2 hours life before I need to plug in. In windows, I get 8 hours or so. My previous laptop (an Asus N750JV) gave much the same time in Linux as Windows. I tried rebooting into a live Mint 18 USB and found I have over 4 hours, but wifi is off and I surf with a wired connection. Still, it's twice what I'm getting now and I plan to switch up soon.

My Alienware tends to have its fans roaring periodically and then they back off.

Powertop gave me this information:

Code: Select all

PowerTOP 2.5      Overview   Idle stats   Frequency stats   Device stats   Tunables                      

Summary: 1078.6 wakeups/second,  2.0 GPU ops/seconds, 0.0 VFS ops/sec and 8.9% CPU use

                Usage       Events/s    Category       Description
             66.0 ms/s     823.6        Process        /usr/lib/firefox/firefox
            100.0%                      Device         Audio codec hwC0D0: Creative
              3.6 ms/s      73.3        Process        /usr/bin/X :0 -audit 0 -auth /var/lib/mdm/:0.Xauth
            165.8 µs/s      44.9        Process        [rcu_sched]
              3.5 ms/s      27.4        Process        cinnamon --replace
            544.5 µs/s      23.4        Timer          tick_sched_timer
              1.4 ms/s      11.7        Process        gnome-terminal
              1.1 ms/s      11.7        Interrupt      [6] tasklet(softirq)
            184.4 µs/s      10.7        Process        nemo -n
            119.8 µs/s      10.7        Process        [rcuos/0]
            170.4 µs/s       9.8        Process        [rcuos/2]
             65.1 µs/s       9.8        kWork          ieee80211_iface_work
            494.7 µs/s       5.9        kWork          os_execute_work_item
             57.7 µs/s       3.9        Interrupt      [131] i915
              7.2 ms/s       1.0        Timer          hrtimer_wakeup
              2.8 ms/s       2.0        Process        powertop
             36.3 µs/s       2.9        Process        [rcuos/4]
             36.2 µs/s       2.9        Process        [rcuos/6]
             61.8 µs/s       1.0        Process        [nvme]
             39.1 µs/s       1.0        Process        /usr/lib/accountsservice/accounts-daemon
             20.2 µs/s       1.0        kWork          flush_to_ldisc
             11.1 µs/s       1.0        Process        /usr/bin/ssh-agent /usr/bin/dbus-launch --exit-wit
              2.5 µs/s       1.0        kWork          vmstat_shepherd
            346.4 µs/s      0.00        Interrupt      [150] nvidia
            286.0 µs/s      0.00        Interrupt      [7] sched(softirq)
            232.4 µs/s      0.00        Interrupt      [1] timer(softirq)
            227.9 µs/s      0.00        Timer          process_timeout

<ESC> Exit |                                                                                             

- but I lack the knowledge to interpret it. If anyone could help, I'd really appreciate it.

[jimallyn]

You might try installing tlp on it.

http://linrunner.de/en/tlp/docs/tlp-lin ... ement.html

[sikejsudjek]

TLP should fix it. It can be installed without configuration - but you can also set it to do things like turn off dvd drives and unused card readers in battery mode. Unfortunately there is no gui, but the instruction are pretty simple to follow for its config file.

Other things you can try. I find on my laptop that chrome is pretty heavy on the battery. For most general web browsing I use midori browser which appears to use about 8w's less. Turning off unused ports in bios can help. Check that any graphics cards are in adaptive mode on battery not high performance and that speedstep and c states are enabled in bios.

[Metal Mick]

Thanks all, I shall dive into BIOS and see if I can find speedstep, although I don't recall seeing it.

I have TLP installed. It made no difference, but maybe I need to tweak it a little. EDIT: no, I did not have tlp installed. I was certain that I had, but when I decided to try tweaking its config file, I found it wasn't there. It most certainly is now, though.

My machine has no optical drive. I only have Firefox in Linux.

I'm not sure what "c state" is though. Is it possible you meant "csm"? That's what google threw up.
Cheers,

Michael P

[Metal Mick]

Installing TLP made some difference - I now have close to 3 hours, but that's still quite poor.

I think I might try installing Mint 18 to see if there's any difference - all my data is safe, so it might be an hour well-spent.

[Metal Mick]

I installed Mint 18, and found little difference to the battery life. Installing tlp made a marginal increase.

I also found that switching back to the Nouveau driver increased battery life by almost 100% - to around 6 hours, maybe more, over the nVidia drivers for the Intel gpu. Performance difference between Intel vs Nouveau is negligible. For example, in 0 AD, I get between 20 and 30 fps for either, but with the 970 running, I get around 100.

It's a bit strange because I was getting 4-5 hours from my Asus 4th-gen i7 with a 62kWH battery, but the 97 in my Alienware isn't yielding the battery life increase I was hoping for. Perhaps it's because the Dell is a gaming laptop, but I'd expect that to be a bit better at eking out a bit more battery than a 2-generations-older machine, quite apart from the 50% larger battery.