Re: PC Power Consumption

"Phil Weldon" <> wrote in message
news: m...
>A few months ago I posted about a AC electrical power meter I'd found
>advertized for $18.95. I just purchased one, and have found it useful and
>accurate. My initial idea was to use it to check PC power consumption for
>different operating modes and loads. But what with the surge in energy
>prices ...
>
> The manufacturer is P3 ( www.p3international.com ). I bought Model P4400
> Kill A Watt. This is a US/Canada model, 125 VAC 50/60 Hz 1875 VA Max.
> The unit is about the size of a box of kitchen matches, LCD screen and
> control buttons, a three prong AC receptacle on the front and a 3 prong
> grounded plug on the back. The AC connections are standard NA, two
> parallel blades for hot and neutral and a round ground pin.
>
> Only one drawback in use. This model has no internal battery, so you can
> only read data while it is plugged in to AC power, and the data store is
> lost when the unit is unplugged. This is especially a shortcoming when
> you attempt to use it in a wall receptacle a few inches above the floor.
> In aid of not crawling on my belly, I use a short extension cored B^)
>
> Reporting capabilities:
> Volt
> Amp
> VA
> Watt
> Hz
> Power Factor
> Kilowatt Hours
> Elapsed Time.
>
> I used the unit with my Windows Vista Home Premium / E4400 @2.7 HGZ & 1.25
> v / 2 X 1 GByte Patriot DDR2 1066 / EVGA 680i / EVGA 8800 GT 320 MByte /
> Antec Neo 550 Watt modular power supply / 2 X 500 GByte Seagate 7200 RPM
> SATA / DVD R/W/RW / CD-ROM R/W/RW / Creative Fata1ity Platinum system.
>
> I was pretty amazed at the small difference in power consumption between
> idling along and heavy CPU / Graphics loads. With no power saving
> features or throttling, about 195 Watts at idle and about 225 Watts under
> heavy load (monitor and other external peripherals not included, drives
> not heavily in use.) So, while waiting for Nehalem, I think I'll
> investigate PC power usage. Here in Atlanta, for the moment, my per KWH
> charge is about $0.08 US, so an hours computer use is about $0.016. Not
> much IF YOU TURN YOUR SYSTEM OFF WHEN NOT IN USE. But I've left my system
> on when not in you more than I should have (think distribute computing
> projects.) I'd always assumed that there'd be a big difference between
> power consumption and high load power consumption - but that evidently
> isn't always the case.
>
> And $0.016/ hour X 24 hours X 365 = $140.00, and in my case that's without
> monitor, modem, or wireless router. And more in a year than the purchase
> cost, March 2007, of my CPU!
>
> Phil Weldon
That is interesting and surprising that the difference between idle and
heavy load is so small. Our power rates are somewhat lower (vary between
5.0c-6.5c KWH) with a rural co-op, but still a substantial amount over a
year. My system probably makes up that difference in price because I am sure
it will use much more power with the two video cards, water pump, DSL modem
etc. I also have a Samsung 24" LCD that probably uses more electricity than
most would think. Have you set up Vista to go to sleep mode and see what
kind of power usage you get? I am waiting on Nehalem too and will probably
not do another build until after Xmas.

Ed