Low-power PC

by **Digit** » Tue Oct 17, 2006 9:45 pm

Hi all,

With an increasing number of PC's running 24/7 here at home, i've begun searching for PC hardware that combines good performance with low power consumption. The 3 always-on PC's are good for 200 W and i would like to bring this number (the 200, i mean) down...

But, it's not always that easy to find information regarding power consumption for the various components needed like mainboard+CPU, harddrive, video card and so on.

As a little experiment, i've decided to put together an experimental PC based on the AMD Geode CPU (14W @ 1.4 GHz), an efficient PSU, 1 hard drive and see what that will bring me in terms of power consumption.

I was wondering if anyone already has some experience in this area or has some really good suggestions?

Regards,
Robert.

by **Bwired** » Tue Oct 17, 2006 10:16 pm

Hi Robert,

I have the same problem, my server is consuming 140 watt, but I'm running a web server with more then 20.000 visitors a month which can not be hosted on the little ones :-)

But running in a home environment they are oke!

We have found a nice list of suppliers of micro/mini computers. Some embedded etc.

http://www.bnc-distribution.nl/producten/ebox
http://www.okaphone.com/artikelen.asp?id=977&groep=680
http://www.norhtec.com/products/mcr/details.html
http://www.ipcmax.com/index.php?cPath=2 ... 430a225205
http://www.hpsindustrial.nl
http://www.micropower.nl
http://www.mini-itx.com
http://portal.homeautomationeurope.com/hae/hcb
http://www.homeseer.com/products/pro_series/index.htm

and a topic:
topic.asp?TOPIC_ID=120

Pieter Knuvers
www.bwired.nl Online House in the netherlands. Domotica, Home Automation.

by **b_weijenberg** » Tue Oct 17, 2006 10:38 pm

The attached file contains an excel sheet with some fan less PC's.
Looking to the cost of a completed fan less system then a laptop is sometimes a good alternative. You have a system, keyboard, screen and a battery backup for less then a fan less system. Problem is that the interfaces possibilities are limited to PCMCIA and USB.

<b>Download Attachment:</b> [url="http://www.domoticaforum.eu/uploaded/b_weijenberg/2006101722316_fanless.zip"][img]images/icon_paperclip.gif[/img] fanless.zip[/url]<br />5.63 KB

by **MindBender** » Tue Oct 17, 2006 11:15 pm

I suppose we all have that problem. I'm running a dual PIII-Xeon/550MHz machine with 1GB ECC memory, 1TB on 3 harddisks, dual redundant power supply. It's switched on 24/7, running Windows 2003 server for my back office and as an internet router. Soon it will run home-automation software too. It consumes about 85 Watt of power. A Watt/year costs about 1,50 Euro here, all inclusive, bringing this machine's consumption to cost 128 Euro per year.

Low power is nice, but components are more expensive and will perform less. If you do really well, you could build a computer that will consume about 30 Watts in average. It will spin down the harddisks, so it will respond a bit sluggish, but you will be able to work with it. Compared with my server, it will save you 82,5 year on electricity. This may sound like a lot, but it's really not that much. If you replace your computer every 4 years, it will save you 330 euro in total. And building a low energy PC will cost you about 200 Euro extra, for a slower machine. So the 130 you save in 4 years with a slower PC made me decide not to do it. However, if you're an idealist it can be interesting. Take a look at the VIA EPIA boards and desktop boards that support Centrine processors.

Personally I'll upgrade to a more powerful machine. It will consume slightly more, but it will also be able to record/stream TV with 4 tuners so it can act as a TV front-end. Using light clients, I can watch both live and recorded TV all around the house. And this way I only need one PC to run 24/7.

by **John Downe** » Tue Oct 17, 2006 11:58 pm

The other thing to consider - which you may have already done of course is avoiding having the 3 PCs actually fully powered all the time 24/7. For example, can you put one or more to "sleep" in Hibernate or Standby mode for some of the time. I have found the free Sleeper program at www.passmark.com to be very useful - you can also use Windows Scheduled events to achieve some of the same functionality. I use Sleeper on an unattended PC running HomeSeer when the house is not occupied but I want to keep a periodic eye on temperatures etc - Each 12 hours it wakes up, checks its email for instructions like "Stay Awake", sends a status report, and if all is OK goes back to sleep again for 12 hours.
You could use a similar technique for automated overnight, say, semi-powerdowns.

John Downe

by **Digit** » Wed Oct 18, 2006 12:05 am

Hi,

Thanx for the response! Guess i'm not the only one interested in lowering power consumption...

Main concern to me is that i currently have 3 PC's running:

- Linux Internet gateway incl. email (spam, A-Virus), proxy, NTP etc (300 MHz Celeron, consuming 35W)
- Win2k server as file server, AD, Exchange etc. (AMD 2000+, 768 MB, 800 GB, consuming 100W)
- Home Automation PC. (AMD 2200+, 256 MB, 20 GB, consuming 60W)

The Celeron is EOL and has to be replaced soon. The HA PC is "overdone", actually. So this is a good chance to look at some alternative for both the Celeron and the HA PC. Both will be idle 99% of the time, hardly ever used interactively, but need to last for many years without any problem (i don't like reconfiguring my hardware every 2-3 years...).

But what i personally don't like, is putting everything on just 1 machine. If that one fails...i'm left with nothing!

Currently, when my Win2k server fails, i just reconfigure some things and i'm back online. Same with the Celeron. I just like that feeling....

So, for me personally, "1 big machine" is not really an option.

But thanks very much all of you for your considerations and i'll have a look at the links, files and thoughts you all gave and when my "Geode" is running i'll hook it up to my power monitor and let you know the results...

Regards,
Robert.

by **Bwired** » Wed Oct 18, 2006 12:35 am

The Bwired Webserver (workstation) I use is a DELL Precision 650 Workstation with a Dual P4 XEON 2.8 MHZ,
2GB ECC 266DDR internal memory,
2x U320 300GB 10.000 Rpm SCSI Hard drives
2x Rs232, 4x USB 2.0 and 2x Fire wire.

The system has a additional Specialix 8 port RS232 PCI adapter which gives the server a total of 10 RS232 connections. The system has also a Teles ISDN Telephone PCI adapter and a Hauppauge PCI TV card.

This system is consuming about 140 watt now and is running for 4 years now without any problems. It's big enough to do all other kind of things like a video server and hosting the Bwired website. I have a similar system in spare and will replace it soon. I'm also running Wk2 Server now and will be upgrading then to Windows 2003 server.
The sleep mode is no option for me at all, I have far over 100 devices running and a lot of those devices are reporting status every x minutes. Also lights automatically goes on and off, curtains are opening and closing, energy control is running, Hvac control, smoke sensors, motion sensors, weather station logging, multi camera controls etc.
Regards Pieter

by **Henk** » Sat Oct 21, 2006 10:06 am

Operating a modern home requires energy - lets make an inventory: (it is an indication and will be different for each household ..

ADSL router/modem - 5Watt
WiFi router - 5 Watt
DECT telephone system 5 Watt
Alarm system 5 Watt
Home controller embedded system 5 Watt or PC = 100+ Watt
X10 modules 25 x 1 Watt = 25 Watt
PIR systems (1 Watt/each)
Cameras 5 Watt
Central Heating System - 20Watt (comfort)
Floor heating pump
Electric hot water boiler (10 Watt)
Standby devices (television) 3x5 Watt = 15 Watt
Computer standby 5 Watt
Trafo's - 5x 1 = 5 Watt
Central exhausting 20W

... even a LED with 12V @ 20 mA is 1/4 Watt - don't know how many LED's are on in my house - of course you can replace them with low current led - but the resistor will take most of the energy ....

Total at least 100 Watt going up to 300 W (PC online) - in case the house is equipped with home control devices - a regular house will cost at least 50W to run.

Some part of the "lost" energy will be recovered - special in winter time and will use less energy of the heating system.

Integrating devices is an option like (ADSL+WiFi+DECT) - also consider using embedded system -

Using embedded controllers instead of PC's for home control I prefer the HCB .... only a couple of Watts.

With home automation you may save on energy like switching of the electric boiler or the central exhausting system during absence ... but it will always needs energy to control it.

Henk

by **Digit** » Tue Nov 21, 2006 1:43 am

Henk,

Quite a list you wrote down.

You're absolutely right that Home Automation can help you save on energy. Although that is not my main reason to "do" Home Automation, i would rather not have Home Automation raise my energy costs even higher as they already are. ;-)

So, that's why i went looking for a "low energy PC".

My Geode intermezzo didn't completely satisfie me BTW; built a PC with that CPU, with only the basic components, resulting in a power usage of 60W. Too much(?). Costs for the components were around EUR 150.
OTOH, i have an Athlon Thunderbird 1200 here, that consumes 100W when idle..so..

Did some experiments on the Geode with some tools like s2kctl ("CPU Cooler software") which managed to bring down the power usage from 60 to 50W, but that also gave me stability issues. So, back to 60W again.

I've been looking for a cheap 2nd-hand laptop as an alternative. Around 600-800 Mhz CPU should be able to do the job (gathering all data and putting it into a Database) for me.
But i've already noticed those aren't that cheap either, and the lack of connectivity (RS-232) will become an issue in the future i think.

Further more, an older 735 MHZ Pentium 3 machine already consumes 45W. So maybe i'll just stay with the Geode and put all HA-related stuff on it.

So i'm still searching and trying...maybe, i'll end up with an eBox...who knows...

Regards,
Digit.

by **Digit** » Sun Aug 19, 2007 3:05 am

Hi all...

Well, i don't give up very easily on things that bother me, so here's a follow-up on this topic.

It looked like my Geode-project for a low-power PC failed (60W idle or 50W but unreliable), but the cause for instability has been found recently: the memory module used was defect. I replaced this memory module, and right now this machine is still consuming 60W idle, but with RMCLOCK installed the idle consumption could be brought down to 52W (disk off:48W), as before. But it is stable now. (Power usage at 100% CPU is 67W)

During my vacation my interest in low-power PC's revived, triggered by seeing that most of the Turkish hotelrooms have individual airco and knowing what this would cost, energy-wise. Combine this with with my thought that power usage could be even less then 50W, i could not resist buying a few AMD Athlon 64 X2 3800+ EE SFF CPU's and a Asus M2A-VM motherboard this week. And i was right! It is possible.

Currently i have a PC running on Windows 2003, with before-mentioned mobo and cpu, consuming only 46W idle and 70W at 100% CPU. This comes very close to "older" PC's i have here, like a Celeron 300 linux machine that consumes 35W idle. Even a PIII at 735 MHz with 1 harddisk consumes 45W idle.... but with this mobo/CPU combo i have much more processing power than i'll ever need... (ehhmm, well, isn't that the same i said 20 years ago when i got my first NEC V20-based PC) ???

Nevermind...i think i can get even better results with a more efficient PSU like a PicoPSU, but that's something i'll look at in the next couple of months or so.

Right now, i'm very pleased with this setup and soon (this year, that is) my Home Automation PC and my main server will be replaced by this CPU/mobo combination. Saving me around (100-45) + (60-45) = 70W...

And then there's 1 CPU left for...let's see...a HTPC perhaps?

Regards,
Digit.

by **MindBender** » Sun Aug 19, 2007 10:29 pm

I have been running Windows 2003 successfully on a EPIA 1GHz board with 512MiB of RAM, a DVD ROM player and a harddisk at 29 Watt... Replacing the Harddisk by a 8GiB Compact Flash card saves another 5 Watt (way less than I expected).

by **Snelvuur** » Sun Aug 19, 2007 10:54 pm

So what about storage? You need a bunch of disks for storage. At least i do.. so that kinda leaves me back with a normal pc anyways. Also bought another 20inch, it works pretty nice now with 2 screens, i'am used to it since i have it at work too. (and some games do work with 2 screens which is really nice)

// Erik (binkey.nl)

by **MindBender** » Mon Aug 20, 2007 12:33 am

Storage? Funny that you're asking. I just got myself a NAS: http://www.thecus.com/products_over.php?cid=1&pid=32. It's got currently Hitachi 1TB DeskStar disks installed in RAID1 configuration. And to answer your next question: It does about 50Watt with spun up disks in idle and making it work doesn't cost much more. I can power down de drives, but I didn't give it a chance for that yet. I can even power down completely a configured schedules, but who would want that?
Now it's hard at work. It's on the power meter, together with a 3Com superstack III professional rack switch and a LinkSys WAP54G wifi accesspoint and it does about 75Watts. This week I will add a UPS which will raise my electricity consumption a little more, but it will fulfill all my storage needs.

by **Digit** » Tue Feb 12, 2008 11:20 pm

Having my kWh-meter working for a few weeks now, this topic became "hot" for me again. So time for a little update.
Plans for my new server have changed through the last couple of months, and in the end i decided to virtualise 2 machines.
This evening i built this, to replace my 3 current machines running 24/7:

- The biggest ATX Bigtower i had laying around with 6 internal hard drive bays;
- Asus M2A-VM mobo;
- 4 GB RAM;
- AMD Athlon 64 X2 3800+ CPU;
- 2 x mainstream 160 GB SATA disks;
- DVD-ROM drive;
- Seasonic S12II-380 80+ PSU. (did -10W compared to a regular PSU)

Power consumption is now 49W.

Add to that 4 x WD1000FYPS (aka WD RE2-GP 1TB) disks (total 16W idle) on a Areca RAID controller (11W) the total consumption should be around 75-80W.
I guess i can live with that for the next couple of years, considering the processing power i get (for when i need it), storage x 3 compared to what i have now, power reduction from 200->80 W, and ofcourse an almost completely quiet (and colder) office.

by **TANE** » Tue Feb 12, 2008 11:37 pm

I have almost the same machine running here
Gigabyte mainboard
AMD X2 3800+
2 GB Memory
ATI X700 Video
2 x WD 500 GB SATA HD
1 DVD
Nexus PSU 350

Power consumption when running AMD Power monitor
about 100 watt p/h

without AMD Power monitor
115 watt per hour.

I think Video card is one of the problems...what else can be?

PS: there is a VMware (Server and WS 5) clock bug when running on more than 1 core.
Your clock in the guest system will not be in sync with the host.
The AMD Dual-Core Optimizer will solve this problem
http://www.amd.com/gb-uk/Processors/Tec ... 18,00.html

Who is online