Re: Re: Low power PC

[Kim Wall <kim@xxxxxxxxxxxxxxxxxx>]

Jon Shaw wrote:
> Can 2nd hand PIIIs be relied on? Ironic that building a low power PC
e.g.
> Mini ITX could cost more than a bargain basement PC ? will have to
work out
> how long it would take to consume the money saved in electricity!

I think this is a fairly important point.  Economically, it's hard to
justify spending money on a low-power PC if you happen to have suitable
hardware lying around already, as the cost of new hardware will pay for
quite a lot of electricity.

The environmental argument's dubious... Carbon emissions are a Bad
Thing, but so is electronic waste...

I think you have to actually get some numbers and do the maths, unless
there are other arguments for the new hardware such as larger capacity
disks, or lower noise (low power stuff tends to be reasonably quiet).

Disconnecting removable drives, underclocking, setting disks to spin
down, recycling the heat, etc. are all good ideas.

One other thing that may be relevant depending on your application...

I have a general purpose file/mail/web/automation/etc server, and my
MythTV backend (containing the capture cards, a decent processor (Athlon
2600 or so IIRC - enough to transcode video without taking all night)
and disks with the video on them) is a separate, considerably more
power-hungry, box.  I have it set up so that the server powers up the
mythtv box by wake-on-LAN when it's time to make a recording, and
frontends do the same when someone wants to watch anything.  MythTV
powers itself down automatically when inactive.  Given the amount of TV
we actually watch, it spends >90% of the time switched off.  A friend of
mine has a similar MythTV setup, based around a Mini-ITX machine which
is powered up 24/7.  It seems unlikely that his uses less power overall.

In other words, changing the duty-cycle of a server may be a better way
to save power than switching to low-power components.  Especially if the
household spend a significant proportion of the day at work or asleep.
This is probably limited to things like media servers, file servers,
backup servers, that sort of thing, though.  Routers, webservers,
Geovision, whatever controls your heating, etc tend to need to be on :)


Kim.