Recently I have been having problems with power consumption in Ubuntu, I am not exactly sure when this started but roughly about two weeks ago. Idle my laptop used about 9-10W of power, or at least it has done for the past two years. Recently it uses 16-18W and I have been trying to find out why. Using powertop it seems that my Network Interface is using 10W+ constantly even when not in use i.e. cable disconnected.
I have even seen it go as high as 30W for Network Interface: eth0 (r8169). Which seems like maybe a fault with PowerTop but my power usage reported elsewhere rises by the same amount.
I am not an expert but this seems queer. Is this normal and just something that I haven't noticed before?
It seems odd that Wifi uses barely any power but Ethernet uses a staggering amount, typically about 9-10W making my power usage roughly double what it was.
Things I have tried:
- Using another driver for my network card – this seemed to drop power to around 5-7W mainly on the upper end of that but I didn't really use it long enough to test properly
- Used an older kernel – no effect whatsoever.
Is there a way to correct this behaviour if it isn't normal?
I have added the services that were discovered by Zenmap:
I have an Apache server running and also have a local Windows network, unfortunately I don't see anything untoward.
—EDIT—
I have just disabled networking via Network Manager and in PowerTop the Network Interface eth0 disappeared from the list, however the discharge rate did not go down by the same amount that eth0 was taking up (about 9W when networking was disabled) so it does seem that PowerTop is misreporting eth0's power usage. I've added a screenshot below.
Even so something is using more power and not appearing in PowerTop.
Best Answer
Well I have discovered what was causing my problems. Firstly it seems that PowerTop is misreporting power usage, the numbers never seem to add up, even after resolving this issue they still don’t.
It turns out that this issue was due to the recent update of the Intel drivers via the Intel Graphics installer. I also had Nvidia drivers and Nvidia Primus for my Nvidia card and it seems somewhere along the way they were either conflicting or had messed each other up.
Firstly I removed the Intel Drivers following the instructions in this Ask Ubuntu answer
This downgraded my drivers but didn’t completely resolve the issue. It seemed that my Nvidia card wasn’t completed being turned off, so I removed all the Nvidia drivers using:
Then I installed bumblebee instead following the instructions in this Ask Ubuntu answer
Once that was done I rebooted and my Nvidia card was definitely off and my power usage was back to normal.
Ethernet power usage still seems high even at 3W, especially as I was using wifi at the time, but I think that PowerTop is just reporting it wrong. Apologies to anyone who spent time on this, I should have realised it was the graphics drivers but PowerTop threw me.