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

Chris Whitehouse cwhiteh at
Mon Aug 11 23:47:02 UTC 2008

Gary Kline wrote:
> 	Folks,
> 	Actually, I have two 'general-computer' type questions, but it
> 	might be better to ask them in separate posts.
> 	First about FBSD (6.x or 7.x) and newer vs older computers.
> 	First, 7.0 seems as stable or more so than its predecessor. 
> 	It may even be faster and more efficient.  How much more 
> 	"green" this is isn't a main question.
> 	But let's take my 1998 Computer each maxed out with a Gig or
> 	close to and having been upgraded to small 2005 drives. Would it
> 	make more sense from a environmental vp to buy a newer, faster 
> 	servers with probably more efficient drives, or just buy new drives
> 	and stay at the current 400MHz speed?
> 	I kep track on the load on my main server, and it is rarely above
> 	0.20.  If the load is a poor metric of power use, what is
> 	better?  (My new `Watt-o-Meter' is checking the power right now,
> 	but I would like to know what drink the most juice: disk,RAM,
> 	processor, OpSys?  Number of hit/hours? I want my upgrades to
> 	be as cost-effective as possible, in other words. 
> 	thanks in advance,
> 	gary

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. 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.

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.

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.

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


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