general questions about 7.0 and computer efficiency......

Chris Whitehouse cwhiteh at
Tue Aug 12 22:52:43 UTC 2008

Gary Kline wrote:
> On Tue, Aug 12, 2008 at 12:46:56AM +0100, Chris Whitehouse wrote:
>> Hi Gary
>> Just back from hols so hope I'm not too late to add 2c. If you do go for
>> new machines it's worth doing some research. I found there's no single
>> component to go for when aiming for energy efficiency, you need to look
>> at them all. 
> 	tHis was the point one person made, and of course it makes sense
> 	to weigh every variable.  Including use patterns.  E.G., I've cut
> 	my personal hacking way down, save for PHP, but still build most
> 	things during a portupgrade.  

Yes usage is important too. A binary port upgrade system that works so 
well everyone prefers it to the source port upgrade system could save a 
lot of energy.

>> I made energy efficiency and silence the top priorities
>> when researching parts for my current desktop and the two pretty much go
>> together. I ended up with Asus M2NPV-VM motherboard and AMD 35watt cpu
>> and Seasonic high efficiency power supply. The CPU is even lower power
>> than AMD's low power range (search for ADD3800CUBOX). It was cheap then
>> but they are hard to find now. There seems to be a lot of variation in
>> CPU power consumption in CPU's with the same performance, eg
>> ADO3800CUBOX, virtually identical, is 65 watts.
> 	Do you build your hardware from the tower case up?  ---Green is 
> 	"in" these days; so maybe some of us, or each of us, can
> 	contribute to a best-of list for those who are going to find a
> 	local builder or roll their own.  First time I'll be in an "in"
> 	group :-)

Yep, any old crap case found on the street will do. With a little care 
building modern hardware is _really_ easy, it's very hard to mess up as 
there is only a handful of parts and most things that plug into other 
things can only do so one way and things that aren't supposed to plug 
into each other mostly can't. Power supplies provide instant protection, 
ie won't turn on when there is a problem. My computer has one each of 
motherboard, hard drive, power supply, optical drive and cpu, plus 2 ram 
modules and a few cables.

The time consuming part is researching the parts. If you are building 
servers you might have to dig even deeper, eg

>> You can also reduce consumption by choosing an energy efficient model of
>> power supply and by choosing lower output power. I calculated the power
>> consumption for each component and found I could buy the smallest power
>> supply in the Seasonic range and still have power to spare. Only one
>> hard drive of course. I bought SATA but it turns out IDE uses less
>> power. Also limiting the amount of memory and keeping the monitor
>> brightness turned down keeps power consumption down.
> 	Hmm, any idea if a large drive  <= 200G is more/less watts 
> 	than having, oh, 4Gigs of ram??

No but I would guess hard drives use somewhat more (depending on whether 
you are using memory intensive or disk i/o apps). Reading manufacturers 
data sheets is the only way to really know. You can find lots of info 
with your favourite search engine.

>> It's a while since I measured the power consumption of the finished
>> machine but I seem to remember it uses about 35 watts at idle and about
>> 95 watts while exercising everything to the max. The Dells at work use
>> quite a lot more, in the region of 60 to 130 I think.
> 	Not that bad if you've got only one box.  My Ubuntu is a bear to
> 	reboot, sometimes, because the mouse goes nuts every other
> 	reboot.  

Do you mean it's not that bad that one computer uses 130 instead of 95. 
I think that is critical to the problem. To think about climate change 
you have to multiply your negligible contribution by the total number of 
negligible contributions. Manufacturers are not interested in 'green' so 
we have to do it for ourselves. I have to say it was a bit painful 
spending £50 on an energy efficient power supply instead of £15 on a 
standard one, but the other parts aren't any more expensive.

I'll redo my measurements in the next couple of days.

>> It's a good idea to turn computers off at the wall when not using them
>> not just shut them down. I was surprised to find mine uses about 25
>> watts when shut down. Again the Dells at work use even more. The
>> corporate environment must waste so many megawatts...
>> For servers my workplace is heading towards fewer physical machines and
>> running virtual servers to implement their 'green ICT' policy.
>> It's great to hear that someone else is thinking about the environmental
>> effects.
> 	I've been thinking about my footprint ever since talking to a
> 	friend up in Ottawa who was looking into building a hay-bail
> 	home.  This is [tiny] green [/tiny].  Hay-bail insulation is
> 	[HUGE] Green [/HUGE].  I told him I was going to buy some land
> 	north of Nome and plant palm trees! 

I've just come back from the climate camp at Kingsnorth in UK :)

Sorry getting OT again but I do think energy use is an issue that we 
should be addressing and has to be addressed on an individual basis.


> 	gary
>> Chris

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