Ideas for reducing PC power consumption

Clocker

Storage? I am Storage!
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I'm looking for any ideas you might have for decreasing the power usage of my WHS box built out of old/spare parts. Here's how it is configured right now:

Processor: AMD 4000+ Socket 939 (downclocks to ~1.15v and 1000Mhz with COOLnQUIET Enabled
CPU Heatsink: Scythe Ninja passive cooler
Motherboard: Asus A8R32-MVP-Deluxe (ATI RD580 chipset)
RAM: 1.5GB DDR400 (1GB + 512MB)
Hard Drives: 3xSATA (250+250+160GB) + 1xIDE(320GB) (total 980GB)
Video Card: None (removal of the 7300GT I had was good for about 20W reduction)
Optical Drive: None (removal was worth about 2Watts)
PSU: Antec SP-500
Fans: 2x120mm close to the Ninja
Case: Antec P180
O/S: Windows Home Server with PowerPack 1

With the drives spun up, it consumes 82W. With most of the drives spun down, its about 67W, IIRC.

One option I can think of is to put it in S1 standby and wake it up as required with a magic packet. In S1 mode, it consumes about 52W. S3 does not seem to work for me, the system just restarts when I try to put it into S3 standby.

Can you guys think of any ideas for reducing power consumption that will pay for themselves in less than a year? I could try removing the fans since the system is in my basement (about 68F at the warmest time during the year).

Thanks,
C
 

ddrueding

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The fans would be good for 3-4 watts, not really worth the risk. The biggest improvement would be to replace all those drives with 1 or 2 drives, bonus points for using 2x500GB 2.5" in RAID-1 for data protection. That would save you a whole lot.

Paying for itself? I don't think so.
 

Fushigi

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I'd do a single TB drive w/o RAID and back up to the old drives in either a caddy or external chassis. You can easily kill one of the fans and, given that power consumption, probably the other or downsize to an 80mm. Remove one stick of RAM if it doesn't increase swap file usage. Use the highest efficiency PSU you can find, and also drop to one with considerably less wattage capacity (you're driving your 500W PSU at under 20% .. probably not very efficient at that load level).

But honestly, you're in the one lightbulb-equivalent category for consumption. It's also about what an average laptop will draw (most come with 65-90W adapters). How low do you think it can go?
 

Clocker

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I'll pull the 512MB stick of DDR, unplug the fans and monitor temps to see.

I don't expect to get much lower than where I am now but I just want to be as good as possible without spending any amount of $ that won't be recovered in savings. I'm wondering how much replacing the PSU will be good for? I think the newer HE ones won't pay for themselves and the M/B has the 24-pin power connection...
 

Bozo

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I replace my power supply with an Earthwatts unit. Notice a dip in the electric bill. The power supply is 80% efficient which means it is not using electric to produce heat. It is also Power Factor corrected which means you are not consuming electric to be able to consume electric.

Bozo :joker:
 

P5-133XL

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I agree, you probably can reduce significant power by using a high-efficiency PS, around 250-300W. Something like this -- SeaSonic SS-300ES. However, I really don't know how long it will take to repay. You need to do some calculating with a kill-a-watt; your local power rates; and a reasonable estimate as to how much time it will stay on.

Yes, replacing all those HD's will save power, but again the question is how long for a payback considering a TB drive will cost $160; two 750GB will cost $200; two 500GB will cost $130. Dropping a drive will save around 10W so it may take quite a while to get the replacement drives paid for by energy savings. I suggest that you calculate it out.

If you are already at 82W I think that it is very unlikely to get a reasonable payback for almost anything that costs $$$.
 

P5-133XL

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Just to clarify.

at 82W if you operate it at 24x7 if will cost only $72 per year at $.1/Kwh. So if you just turn off the machine saving all the energy you will save $72. year. If you save 10W of power, then you will save only $8.70 in an entire year of continious operation. If you operate it only 8 hours a day, then that drops from $8.70 to $2.9 per year of savings. How are you going to pay for a power supply or a HD at those rates in a reasonable time-frame?
 

LiamC

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Don't get hung up on high efficiency power supplies. They are only 80% efficient @ 75%~90% load for the most part—you'd need to see a load/efficiency graph over a wide system load. Most "high efficiency" power supplies have their touted efficiency drop off a cliff outside of a narrow band of operating loads, so for a system that spends most of its time idle, you'd want a 145W "high efficiency" power supply :)

Marketing. Gods I hate it.
 

Clocker

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I was not expecting that to work out, Mark. Hence the reason I posed the question.

I may have an older lower wattage PSU in the parts box but will have to check compatibility with the motherboard. It won't be HE but maybe it will operate more efficiently than the 500W Antec.

BTW, I have been using a kill-a-watt and the energy cost numbers you mentioned.

Anybody think of any other freeware I might run on the box to reduce power consumption besides the LightsOut WHS Add-on?
 

ddrueding

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I used to run CrysatalCPUID to dynamically underclock/volt my system. I suspect you currently have your system underclocked/volted as far as it will go, but there is no reason not to have some extra horsepower for a few seconds when you need it ;)
 

Clocker

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The fans were good for about 2.5W total. I removed the more powerful one and plugged the hole for the dead fan. Trying the SL350 Antec PSU got me no-where. I guess this system is as efficient as it is going to get. Now to just monitor CPU temps for a while...

CoolNQuiet seems to do a good job of controlling the CPU automagically.

C
 

Santilli

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How can you tell what the machines consumption is?
Are you using a monitor?
 

sdbardwick

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Don't get hung up on high efficiency power supplies. They are only 80% efficient @ 75%~90% load for the most part—you'd need to see a load/efficiency graph over a wide system load. Most "high efficiency" power supplies have their touted efficiency drop off a cliff outside of a narrow band of operating loads, so for a system that spends most of its time idle, you'd want a 145W "high efficiency" power supply :)

Marketing. Gods I hate it.
Often the peak efficiency is at 50% load. 80+ certified supplies are tested to be at least 80% efficient across a wide range of loads. The 80+ website has testing results (including efficiency graphs) for all of the certified PSUs. JonnyGuru.com and Hardocp.com have good testing procedures for PSUs and their results for efficiency are in line with 80+ results.

N.B.: The JonnyGuru and Hardocp measurements (and most of the 80+) are made using 120V mains; you often get 1 to 3% better results with 220V (or 240V) mains.
 
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