Low power PC option

["Jonathan Shaw" <semi.jon@xxxxxxxxxxxxx>]

As mentioned here before I had been planning to use an old Athlon PC
to run
Idratek Cortex as my HA controller.  In the end when my second hand
Centrino
laptop turned up instead of using that as a domestic PC it seemed easier to
run Cortex on that.  It runs XP with an applet that controls the speed
stepping of the CPU called SpeedSwitchXP.



Having run a couple of tests over night, the PC & Idratek devices (and
a
Dect phone on the same circuit) consume 0.24KWh in 12hours and the spot
checks showed about 20W being burnt.  In the morning the CPU speed is down
just below 300MHz (from 1.7GHz max).  The speed stepping is very fast so
load an audio stream or fire up a browser and it opens as fast as one would
expect  (30W consumed with BT Home Hub + PC + Idratek while streaming from
BBC).  It is not a huge network at the moment 2 sensors 2 relays, over the
coming weeks as I fit more the load may go up, but I am very impressed with
the laptop and how light weight Cortex is.



The flaw in this is lack of expansion, a docking station for the laptop is
available but only takes a half height PCI card, I need a full height one
for the voice modem I have bought!  And another if I am to utilise the CCTV
cable I have run!  I am tempted to buy second hand and attack with a
dremel!
The alternative is to buy a Core Duo PC which has speed stepping and see
how
slow and lean it can run!  The only person I know with a Core Duo and a
power meter has a big graphics card and even at tickover it burnt 150W and
this rose to 200+W when gaming.  Impressive for a machine in a v small case
but it does have to have the disk on the top of the machine else it locks
up!



Has anyone with a Core Duo here tried speed-stepping?



Jon



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