Alright I'll give that a shot, thanks!
As a side question though, is 20W a reasonable idle power consumption for a
high-end recent laptop?
Cheers,
Wout.
On Feb 19, 2014 7:53 PM, "Kok, Auke-jan H" <auke-jan.h.kok(a)intel.com>
wrote:
On Wed, Feb 19, 2014 at 1:13 AM, Wout Mertens <wout.mertens(a)gmail.com>wrote:
> kingma at bluewin.ch wrote on Wed Feb 12 23:32:27 PST 2014:
>
> > I observe a sustained high power consumption of 5- 10 W on the ehternet
> adaptor e1000e on a lenovo thinkgpad t430s. Such I high power drain cannot
> be correct can it? the total power consumption is around 25 W which is a
> concern for battery life.
>
> I'm noticing the same thing on my Dell Latitude E6540. It also has an
> e1000 and powertop reports it as being the highest consumer, at around 15W.
> When I unplug the system, the battery reports a drain of about 20W while
> idle which is pretty bad IMHO. With the 68Wh battery it translates to about
> 2.5 hours battery life.
>
> Lowest I've seen for battery drain is 14W, with the screen at lowest
> brightness, Google Chrome turned off, disk spun down. I'm using the
> built-in Intel graphics and the system has 16GB of ram and a quad-core i7.
>
> I never ran windows on this laptop so I don't know what to expect but
> reviews are claiming 7+ hours on the 90Wh battery. That would mean an
> average of 13W, while doing actual work.
>
> So I'm really wondering: Is the e1000 really eating up 15W or is powertop
> misreporting?
>
There have been plenty of reports that point to the calibration being
incomplete (Let's just call it that).
Obviously e1000 won't eat 15W of power - 15W could power a 10gig Fiber
Optic transceiver (a high-powered laser, basically). Power consumption is
more in the order of a few watts max, with idle power much, much lower.
Calibration could fail if during the calibration phase powertop is unable
to toggle power to components or enable/disable devices. As a fallback, you
can run the calibration multiple times and vary the enabled devices in the
system. You could for instance go into the BIOS and disable the ethernet
device entirely, calibrate, reboot and enable the ethernet device, then
calibrate again. The extra data points should improve the power estimates
for devices.
Cheers,
Auke