how much power does modern PC use?

[akao]

Hello,

Using Watt calculator on http://www.jscustompcs.com/power_supply/
I fount out my PC uses 228Watt + 70Watt for 15' CRT , total is 298Watt
If I operate this PC for 10hours each day, how much will it add to my electric bill in 2 months time?

Local Electric company charges US$11 for 100KWh for 2month.
<a target=_blank class=ftalternatingbarlinklarge href="https://www1.clpgroup.com/ws/en/tariffCalculation/DT/submit.do">https://www1.clpgroup.com/w......ation/DT/submit.do</a>
(US$1 = HK7.8)

I am really at a loss how to calculate this...
Thanks a lot.

 

[dguy6789]

back in 2000, they did a survey and leaving the comp on 24/7, moniter included, that the average power bill increase was under 15 bucks/month

 

[iwantanewcomputer]

298W * (10hours/day) * (60 days) * (1 kWh/ 1000 Wh) * ($0.11/kWh) = $19.67

I'm not sure if i did this right cause i don't know what this means, "(US$1 = HK7.8) "

but it looks right.

 

[wacki]

I have a HTPC, I underclocked the CPU for low heat/power consumption. The power supply is a 300 watt zalman. How do I calculate how much power it is using? Is it still 300 watts each hour?

 

[CSMR]

Originally posted by: akao
Using Watt calculator on http://www.jscustompcs.com/power_supply/
I fount out my PC uses 228Watt + 70Watt for 15' CRT , total is 298Watt

At maximum usage, with leeway.

 

[CSMR]

Originally posted by: wacki
I have a HTPC, I underclocked the CPU for low heat/power consumption. The power supply is a 300 watt zalman. How do I calculate how much power it is using? Is it still 300 watts each hour?

No. <100w probably

 

[Pandaren]

It is not as simple as that calculator makes it out to be. As someone pointed out, those figures are maximum power usage.

First, you would need to figure out average power consumption. This is what your Power Supply would typically have to feed your system as a whole.

Then you need to know the efficiency rating of your Power Supply - If I remember correctly, a basic Antec SmartPower PSU has a conversion rate of at least 68% (the rest is converted into heat waste), but I don't knwo how this rate varies with system demands.

According to that calculator, my system (see sig) would draw ~200 Watts under full load. Assuming that it only uses 75% of this on average, I'll guess that typical power draw is 150 Watts. Assuming a worst case PSU scenario, 150 Watts is 68% of what the PSU would need to get from the wall socket. 150/(0.68) = 221 Watts.

My 17" LCD typically draws about 50 Watts (compared to 100-120 for a 19" CRT of same optimal resolution).

My LCD is on about 9 hours of the day (off when I'm asleep (6 hrs) or not home (9 hrs)). I leave the system unit on 24/7.

For the tower:
221W * (24hours/day)*(30 days) * (1kWh / 1000 Wh) * ($0.06/kWh) = $9.55.

For the LCD
50W * (9hours/day)*(30 days) * (1kWh / 1000 Wh) * ($0.06/kWh) = $0.81.

Total for the tower+LCD is $10.36/month. :|

 

[Shalmanese]

Data point: A SFF PC can power top-of-the-line components under 115W so thats your upper limit on any sane PC configuration. A monitor is going to be outputting the same order of magnitude so figure 100W + 100W total. However, if you set your monitor to auto-power off after 15 minutes or so, your lopping off about 1/3 to 1/2 of your power bill. Either way, it comes to about $5 - $10/month.

 

[Matthias99]

Originally posted by: Shalmanese
Data point: A SFF PC can power top-of-the-line components under 115W so thats your upper limit on any sane PC configuration.

Considering that top-end processors can eat up ~75-100W, as can top-end video cards, plus PSUs are not 100% efficient, this cannot possibly be true. However, no (relatively) normal system is probably going to pull more than 250W from the wall at most (say, 75W each from the CPU/RAM and video card, and 50W for other peripherals, plus taking the conversion efficiency of the PSU into account). If you're overclocking, your power needs can go way up (particularly with voltage increases; power use tends to increase as <voltage>^2 * <frequency>, or even <voltage>^3 * <frequency> for some kinds of electronics -- and that's not even taking things like leakage current into account).

If you really want to know how much power you're using, get a wattage meter like the "Kill-A-Watt" that Radio Shack sells. Newegg also carries a couple of them, I think...

 

[FrankSchwab]

An interesting article over at TechReport might answer the question for you, at least for top-of-the line configurations.

Slashdot had a quick blurb on this report this morning, just before I read this question.

/frank

 

[imported_StormGod]

Originally posted by: Matthias99

Originally posted by: Shalmanese
Data point: A SFF PC can power top-of-the-line components under 115W so thats your upper limit on any sane PC configuration.

Considering that top-end processors can eat up ~75-100W, as can top-end video cards, plus PSUs are not 100% efficient, this cannot possibly be true.

We also need to consider what the processor is doing in any given day. Sadly mine seldom sees more than 1% load anymore as all I do is email/internet. Now if I was folding 24/7 I would use *much* more juice than I do now.

 

[DrPizza]

Another important consideration is conservation of energy.

Unless you somehow have your computer vented to outside your home, in the summer those 200 or so watts are being converted to heat. If you're using air conditioning to maintain the temperature of your house, the air conditioning unit is working a little harder to cool in the summer.

On the other hand, in the winter, your computer is helping to heat your house. So, if you're using electric heat, you can almost ignore the power your computer is using since a very high percentage of it is also being converted to heat.

 

[imported_StormGod]

Except that electrical resistance heating is very inefficient when compared to direct combustion of heating oil.

 

[TuxDave]

Originally posted by: iwantanewcomputer
298W * (10hours/day) * (60 days) * (1 kWh/ 1000 Wh) * ($0.11/kWh) = $19.67

I'm not sure if i did this right cause i don't know what this means, "(US$1 = HK7.8) "

but it looks right.

*golf clap*