The Power Consumption of Modern PCs

janp writes "The power consumption of modern PCs has skyrocketed the past few years. Hardware.Info has done some fairly extensive research on the power usage of various configurations. It turns out the a high-end gaming rig can easily use more than 400 W, and that putting a system in stand-by isn't as saving as you might think. The article has some interesting tips to save on power costs."

Comments

Conserving energy by not using applications

[Radon360]

I think the author of this article tried conserving energy by not using spell check.

Get Laptops or smaller

[Salvance]

If you're worried about power consumption, you're not going to buy a top of the line gaming rig. You'd probably buy a relatively low powered laptop (or even buy a very underpowered laptop similar to a OLPC machine). Gaming machines will continue to be bigger and bigger power hogs. More power consumption = faster and better gameplay, no way around it.

Re:Get Laptops or smaller

[tomstdenis]

Not really. more crap in game IMPLIES more power, but compare say a 486 to a Core 2 Duo. The latter is much more efficient per MIPS than the former.

To put it another way, to match the power [in MIPS] of a typical 1989 486 desktop, you could do so with far less power consumption today. The problem is few companies write conservative software. Go ahead, make your application inefficient, a new cpu is always around the corner!

What people seem to forget is that we were doing word processing, vector graphics and all that on old school Mac IIs in the mid to early 80s. Those programs certainly didn't require hundreds of megabytes of ram or gigabytes of disk space. Of course people associate numerical requirements with quality. CPU has more megahurts? It must be better! Game needs a faster GPU? It must be awesomer! etc...

I'm personally impress with efficiency not bulkyness. Write me a competent word processor that fits on a floppy disk. That'd be a hoot.

I just did some research on this actually

[casualsax3]

A few weeks ago I tested some power supplies to see if it's worth spending $70 on a power supply vs the crappy stock PSU that comes with a lot of cases you can find on NewEgg.

I used Kill-a-Watt power tester, which can test for a number of things - I used raw amps.

I tested 4 machines with 5 power supplies in 0, 1, 2, 3, and 4 drive configurations. I also took a reading of how much power the systems drew when I powered them on at 4 drives, which shows how efficient the power supplies become under serious load (it takes a good chunk of power to spin up 4 drives)

The machines were all tested with the same 1x1GB PC5300 RAM, and the same four Western Digital SATA drives. The Intel systems were LGA775 chips on an Asus, and the AMD's were AM2 - also using an Asus motherboard.

Here are the results (hosted by Voxel.net, so it should hold :) http://newyorkhatesyou.com/Power_Supplies.pdf

Power supplies tested: http://www.newegg.com/product/product.asp?item=N82 E16817256001

http://www.newegg.com/product/product.asp?item=N82 E16817371006

http://www.newegg.com/product/product.asp?item=N82 E16817151022

http://www.newegg.com/product/product.asp?item=N82 E16817234002

In a lot of cases the stock power supply uses almost twice as much power.

In Brooklyn I pay $.19c/kwh, so 1 amp of power can cost around $20 a month - ((volts * amps) / 1000 ) * time (in hours). This means pretty plainly, that the stock PSU here would cost me another $15 per month on my one desktop that I always have on.

Now if an office switches all of our workstations to one of the three 80% efficient power supplies, we stand to save a few hundred per month. Add to that the fact that these power supplies generally have more stable rails, and they should last longer - and its really a no brainer.

Re:I just did some research on this actually

[Spoke]

One other guideline when purchasing a PSU:

Buy the smallest PSU possible!

Many people out there have "SUV syndrome" when buying a PSU and incorrectly assume that they need that huge 500w (or bigger) PSU for their PC. Unless you really do have a high-end gaming PC with a high-end graphics card and multiple hard drives, your computer will almost certainly normally use less than 200w peak, and more typically 75-150w.

What does happen with an oversized PSU is in order to build a PSU to handle high current, it's efficiency at low current drops significantly. Typically the efficiency of a PSU starts dropping pretty quickly below 50% capacity and even faster below 25% capacity.

Finally, you can also look for PSUs which are 80 PLUS certified. These PSUs have been independently tested to be at least 80% efficient at 20%, 50% and 100% loads with a power factor rating of at least 0.9 at those load points.

The Antec EA430 is part of Antec's EarthWatts series of PSUs which are all 80 PLUS certified.

Out of the other PSUs casualsax3 tested, the SilverStone SST-ST50EF is also 80 PLUS certified. I could not verify if the Seasonic S12-380 is 80 PLUS certified, but it does not appear to be so even though it is more efficient than the Silverstone in casualsax3's test. If the S12-380 is of the "S12 Energy Plus" series then it should also be 80% efficient. I wonder if Seasonic quietly started shipping Energy Plus S12s instead of the old ones...

Re:No your math is wrong (follow up)

[Darkfred]

Obviously I bought a new refridgerator. A 10 year old refridgerator is just not efficient anymore.

But the scariest thing I found during my power audit was that each incandescent lightbulb was taking more power than my computer at rest. A single chandelier in my house accounted for 1/4 of my electrical bill.
By replacing all the lightbulbs with compact flourescent I was able to shave a 3rd off my monthly bill. (still quite high because of an old ac system).

In conclusion your computer is such a minor contribution to electricity that you shouldn't even be considering it before you fix the big offenders.

Re:No Kidding

[alexhs]

They're as 'off' as an ATX can be 'off' with the power supply switch to 'I'. You need a cold boot, but of course you still use some power. It's G2 state

Re:No Kidding

[ashitaka]

No, they can actually be fully "shut down".

On a modern PC with a built-in motherboard you will notice at least one lit LED on the motherboard as long as the PC is plugged in. A tiny amount of power is being provided to the network adapter to listen for "magic packets" which, after being verified, will cause the machine to power up as if you pressed the power switch. This could be from standby or suspend but a cold boot is also possible.

Re:So just don't turn on the heater...

[spun]

Here I pay about 4 cents per KwH. Nice, huh?

So that means you can afford huge sun lamps to combat the pervasive Seasonal Affective Disorder brought on by the constant clouds, eh? I keed, I keed. Seattle's a beautiful place with a lovely climate. All that stuff about rain is just a rumor spread to keep the Californians out. Really, it's sunny all summer long in Seattle. And if summer happens to fall on a weekend, everyone goes on a picnic!