[Arm-netbook] Power consumption

Alain Williams addw at phcomp.co.uk
Thu Mar 4 16:55:21 GMT 2010


Luke asked me to try & get an idea of the power consumption of these arm-netbooks.

I have not really fiddled with mine yet (thanks parcel farce) so these measurements are
done on the install as delivered.

I have a power meter, I plugged it into there so the measurement includes the external
power unit (actually a slightly different one since that has a 3 pin (UK) plug on it).

First running not plugged in, it ran for 2 hours 50 minutes. The screen was on all the time
(did not blank), wifi was on and it was running top & a little script that looped
and echoed the time to the ssh tty and to a file once/second ... until it ran out of
power.

I plugged it in and took some 3 hours 15 mins to fully charge, that time has about 20 mins
or so error on it, since it relied on me noticing that the power tool said charged.

While it was doing that it drew 0.02 amps (at 267 volts !), this was reported as 7 watts,
when the screen was blanked it went down to 5 watts.

Screen brightness did not affect the current drawn, wifi was always on.

It did not charge unless it was switched on (?).

When it was fully charged, my meter reported the current usage as 0 watts.

I don't know if this says more about my meter than the netbook, but whichever way
it looks quite economical.

-- 
Alain Williams
Linux/GNU Consultant - Mail systems, Web sites, Networking, Programmer, IT Lecturer.
+44 (0) 787 668 0256  http://www.phcomp.co.uk/
Parliament Hill Computers Ltd. Registration Information: http://www.phcomp.co.uk/contact.php
Past chairman of UKUUG: http://www.ukuug.org/
#include <std_disclaimer.h>



More information about the Arm-netbook mailing list