Energy efficiency in the 21st century

[GoodGame]

There's no real thread about collecting info on energy efficiency in computing, so I thought I'd start one.

The issues (or why care).

1. Climate change
2. Population growth (more growth = more demand)
3. Electricity Deregulation. Your ELECTRICITY BILL, STOOPID!

#3 is the most important to me right now.


Things we could actually discuss:

1. calculate/measure your techie electricity consumption
2. How to make a rebuild your Desktop PC so it's not an obnoxious power consumer
3. What is the best upgrade option for your user needs (e.g. internet phone, notepad, gaming laptop, desk replacement laptop, etc...)?



******************

I'll start an upgrade situation:

I just moved from a coal-fired, barely starting electricity deregulation state to a "aint got no coal", been deregulated for many years state. So now I pay an electricity bill in a mostly unsubsidized unregulated market. While I eagerly await the first quarterly bill, I'm thinking about what to do with my desktop:

It's a legacy Intel core duo E8XXX. Its on a bronze rated energy efficient 520W power supply. It's got a legacy GPU without fan (heatsink)---about 2006 quality. It's got several harddrives and 1 optical drive, and an internet card.

So how do I throttle this thing to make it more energy efficient?

1. go back to an earlier E8XXX with lower consumption / or tweak the clockspeed to a lower setting?

2. Remove hard drives to external carriages, and only turn them on if needed?

3. Take a chance a lower rated power supply that is still bronze rated or better? (This is actually a cheap option ~$30, and just return in the mail if it undervolts causing system instability).

4. Upgrade to 7?

 

[Genocidicbunny]

Hard drives in a standby state draw barely more power than if they were off. On the order of a couple W-hr. The biggest power draw from them comes on boot. After that, it decreases quite a bit.

For a PSU, no, you want to be in the 70-85% utilization zone for the PSU. That is where they are the most effective. A lower-rated PSU may seem to fit better, but if its in the crappy efficiency zone, for every watt your computer draws from it, it will draw more from the socket than with a PSU that's in that sweet spot.

What you can do -- get a more efficient GPU. Yours may be drawing X watt-hours, but a more modern CPU of similar quality and performance will draw a lot less power. They may also be able to throttle down a lot better. Same goes with a CPU. CPU power draw has not increased by that much in the last decade, so nowadays you get a lot more performance per watt. This means that for the same tasks, a newer CPU may not need to throttle up fully thus saving power.


If you really want to save electricity, make sure your computer throttles down when idle. Hibernate/shut down when not using it, have monitors go into sleep mode after some amount of time.
OR, get a laptop. It will draw a lot less power, be more portable, and if properly chosen, just as usable.

 

[Cutlass]

Did you move to California or Connecticut? Your PC might not be the best place to save electricity. But the main thing is to have it off when not in use. And that includes all the accessories. APC advertises a UPS that saves power to the whole setup. Not sure about that, but worth investigating.

Everything in your setup draws some current when not in use. And many accessories, like routers, speakers, and printers, have external transformers that are always drawing some power. I connect them to the UPS rather than a separate power strip. So once closing down the PC, I shut off the UPS, and there is nothing connected to the PC drawing any power at all.

That standby power, and your TV, DVD player, stereo equipment, and many other things do it as well, adds up to a lot of juice.

 

[Zelig]

That standby power, and your TV, DVD player, stereo equipment, and many other things do it as well, adds up to a lot of juice.

Standby mode on devices should add up to about $3/year/device or less in electricity costs.

 

[aimeeandbeatles]

I read somewhere that cheap PSU's waste more energy by converting more of it to heat. I dont know how true this is though.

 

[Genocidicbunny]

A PSU is not 100% efficient so some of the energy it draws in is indeed dissipated with heat.

This is why you want to get a PSU that will be in that sweet spot for it's rated power output between like 60-75% output utilization. It is most efficient there.

 

[Zelig]

I'm hoping we see more quality power supplies with numbers like the Kingwin 550W:

Load W; Load %; Efficiency%
152; 27.6; 90.48
283; 51.5; 92.18
412; 74.9; 91.35
559; 101.6; 89.58

 

[aimeeandbeatles]

A PSU is not 100% efficient so some of the energy it draws in is indeed dissipated with heat.

This is why you want to get a PSU that will be in that sweet spot for it's rated power output between like 60-75% output utilization. It is most efficient there.

Well from what i understand the cheap PSU's have a lower efficiency (maybe not the right word) so a higher percentage of power is wasted as heat than you would with a better one.... Like a cheap one might waste 40% of the energy going in, while a good one might be 10%.

 

[Genocidicbunny]

Exactly. The cheaper ones may also not meet all the output requirements for the ATX standard as well as a high quality power supply.

@Mars: hot damn those are beautiful numbers.

 

[Hehehe]

For a PSU, no, you want to be in the 70-85% utilization zone for the PSU. That is where they are the most effective. A lower-rated PSU may seem to fit better, but if its in the crappy efficiency zone, for every watt your computer draws from it, it will draw more from the socket than with a PSU that's in that sweet spot.

My PSU manufacturer promises a minimum of 80% efficiency. So yeah a good PSU helps.

or tweak the clockspeed to a lower setting?

I believe Intel SpeedStep automatically underclocks your CPU if it's not in heavy use, thus lowering energy consumption. So I doubt underclocking will do you much good.

 

[aimeeandbeatles]

Ok heres an question: I know if you put your computer to sleep you save substantially more energy than leaving it live or whatever its called. Is there as much a different between sleep and hibernate? I'm kinda strapped for HDD space (you can blame Mr. Petty for that) and the landlords sorta getting after us for using so much energy.

 

[Genocidicbunny]

The difference is not all that significant. Certainly no more than a couple watt-hours.

 

[aimeeandbeatles]

So its better just leaving it standby? Im terribly afraid of running out of hard drive space by putting it in hibernate.

Another thing i noticed is you turn down the LCD and I think that saves power and its also easier on the eyes. Looking into a very bright screen for hours can hurt.

 

[Zelig]

You really shouldn't be cutting it that close for space, that can cause problems both with virtual memory, and with defrag not working.

And I assume everything is backed up, as your hard drive could catastrophically fail at any time.

 

[Narnia]

4. Upgrade to 7?

AT ALL COSTS DO NOT DO THIS
I have windows 7 and don't get me wrong, it is a great OS... it just used WAY too many system resources. If you want green, get an older OS like xp

 

[Narnia]

So its better just leaving it standby? Im terribly afraid of running out of hard drive space by putting it in hibernate.

Another thing i noticed is you turn down the LCD and I think that saves power and its also easier on the eyes. Looking into a very bright screen for hours can hurt.

I recently read an article (forgot where, I think popular science/mechanics however I could be wrong) where they tested this and they found that with modern computers the power difference is very small

Edit: that's strange, sorry bout the double post, I don't know why that just happened

 

[Zelig]

AT ALL COSTS DO NOT DO THIS
I have windows 7 and don't get me wrong, it is a great OS... it just used WAY too many system resources. If you want green, get an older OS like xp

Yeah, don't use XP, it sucks.

That's like recommending to use DOS command line because the black screen will have your monitor use less power.

 

[Narnia]

Yeah, don't use XP, it sucks.

That's like recommending to use DOS command line because the black screen will have your monitor use less power.

Dos would use less power but that's a little too extreme . However, you do realize that windows 7 uses 2 GB of RAM even when it's idling. I don't know how much electrical power that translates into , but I do know that it uses a lot more than xp and even vista.

 

[Zelig]

Dos would use less power but that's a little too extreme . However, you do realize that windows 7 uses 2 GB of RAM even when it's idling. I don't know how much electrical power that translates into , but I do know that it uses a lot more than xp and even vista.

Yes, it uses more RAM because it's a much better operating system.

A module of memory will use about 5 watts regardless of the size, and any modern system is going to need at least dual channel memory, so a 2x8GB Win7 system is going to use the draw the same amount of power as a 2x1GB XP system, while being much faster and more usable.

Furthermore, DDR3 modules take less power than older modules, so a 2x8GB DDR3 system will draw less power than any lower memory system using any sub-DDR3 memory modules.

 

[Narnia]

Yes, it uses more RAM because it's a much better operating system.

A module of memory will use about 5 watts regardless of the size, and any modern system is going to need at least dual channel memory, so a 2x8GB Win7 system is going to use the draw the same amount of power as a 2x1GB XP system, while being much faster and more usable.

Furthermore, DDR3 modules take less power than older modules, so a 2x8GB DDR3 system will draw less power than any lower memory system using any sub-DDR3 memory modules.

Ok, I stand corrected. Thanks for the info