Carbon diet
It is called "Mountain top removal"
def: Mountain Top Removal
February 2006
I don't approve of people destroying Appalachia so we can heat our houses with electricity from coal-fired power plants. So I am putting myself on a low carbon diet.
Carbon saving tools
Article about PowerTop from Linux World : Linux tool points out power-wasting applications http://www.linuxworld.com/news/2007/072707-linux-power-wasting.html?nlhtos=080307linuxalert1&
Conservation begins with data collection
I have to establish a baseline of our current energy use. I will need to log electrical use and temperatures over a period of time.
My house uses gas (and optionally, wood) for heat. It has an electric stove and water heater. Only the antique gas/wood central furnace uses gas.
I can monitor its run time by monitoring the electrical circuits running to it. I don't have a good way to measure actual gas used other than gas meter readings. I suppose I could read the meter once a day and log it. For a simple gas-only furnace, one way to measure furnace use is to monitor the fans; when the fans go on, hot air is being pushed through the burner so the burner is running. My furnace complicates things by having both wood and gas sections, so I will have to address that. (Possibly by replacing it!)
I can install a data logger and current taps at the main breaker panel to get readings on the whole house. See Power measurement page.
Measurements using Kill-a-watt
Computers
HP Vectra desktop
- Astec ATX90-3405 SFX/MicroATX power supply [1]
- HP Motherboard
- RAM
(SFX has no -5V supply so is not ISA compatible. 90W is all the spec requires.)
Via EPIA 800
- Astec ATX90 power supply
Board by itself draws 29W with this supply
Adding the CD drive, draws 3W more when drive checks for CD then drops to 29W
Adding the Vectra HD, draws 34W at boot and then drops to 22W,
so the CPU must still be doing some work when it is unable to boot.
Spinning down the HD drops it to 19W.
What I'd like to do is load up a CF card with the operating system and have the hard drive hold only data, so when the system is idle the drive spins down.
Generic Pentium Pro 200 system
- Powerman 235W ATX supply with on/off switch
- Pentium Pro 200 Intel Mars motherboard
- Four 72 pin 32MB SIMMS = 128 MB
- No CPU fan (power supply fan directs air directly onto heatsink)
- Tulip network card (est 2W)
- Soundblaster Model CT4180 card (2W)
- Dual port Intel network card (3-4W)
- Dual port SIIG USB 1.0 card (2W)
- Trident video card (ISA) (3W)
- Intel Mars motherboard PIIX chipset
- PS/2 keyboard (no difference on power reading w/o keyboard)
- IDE hard drive: IBM Deskstar 15 GB IBM-DTLA-307015
Boot: 55-60W, peaks to 70W
Idle: 36W
HD spun down: 31W
Stripped down: MB + 128MB RAM + HD = 23 W
Spinning down the hard drive saves 5 watts
Power supply has OFF switch; with the various and sundry network cards installed it burns
PS fan and CPU fan died years ago so I put the high quality fan from a Sun 3 workstation into the supply and dumped the CPU fan. CPU does NOT get hot under normal operation.
CDROM drives
Only needed occasionally; I can leave a drive in the system but unhook power to it.
- Diamond 8X CDROM: 1 W when idle (no disc in drive)
Mini-ITX
Update 15-Sep-2008: I have two Mini-ITX systems now, one based on the C7 and one on the Intel Atom. Their names are Bellman and 8track. I need to measure their power usage and update this page.
C3 system
The system tested above based on the Via board is in the Mini-ITX form factor. There are "fanless" and "fan" versions with 500 and 800 Mhz processors. I used an 800 Mhz board and replaced the obnoxious screaming high pitch fan with a fanless Zalman BZ-47 Northbridge heatsink. The case and power supply fans provide adequate cooling. I built the case from 1/8" plywood and hardwood scraps.
I monitored temperatures and turn down the fans using a controller from Sunbeam. This gives me a front panel readout only, no way to monitor from the computer.
Unfortunately the motherboard in this system died, probably due to getting zapped with static in one of the numerous hacks. I have vowed to set up a static free workstation.
C7 upgrade
The C3 processor on the Via 800 Mhz card is basically a Pentium instruction set. Not Pentium Pro or II or III or 4... just "Pentium".
The new C7 processor has an advanced instruction set and it's faster. Does this mean it uses more power? Or is it more efficient. I have gotten a CN10000 board from Logic Supply.
The new board is now installed in a case. For more information, see the 8track page.
CPUFreq
Turn the CPU speed down when you aren't using it!
Two options are cpufreqd amd powernowd I am testing powernowd.
I installed powernowd from the Debian package.
For the C3 processor, enabling speed control means loading the 'longhaul' module and one of the governor module. For powernowd, the governor to use is 'userspace'. From the command line,
modprobe longhaul modprobe cpufreq_userspace
Look in /proc/cpuinfo to see the current CPU speed. Right now I see
processor : 0 vendor_id : CentaurHauls cpu family : 6 model : 7 model name : VIA Samuel 2 stepping : 3 cpu MHz : 400.094 cache size : 64 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu de tsc msr cx8 mtrr pge mmx 3dnow bogomips : 800.57
It's cut the CPU speed to 400 Mhz (normally it is 800.) Now I can drive up the load by playing a movie and check again. Sure enough! When the movie plays I see the cpuinfo report
cpu MHz : 800.189
C7 update I have installed Ubuntu 7.04 on 8track and cpufreq is available as an option. It works fine. There are more notes on the 8track page.
Don't get a C3 board, go right to the C7 or possibly even a Mini-ITX board based on a Pentium mobile processor.
NOW... I need to know more accurately just how much power this baby is using. I need some instrumentation! Power measurement
Linux on Compact Flash
http://silent.gumph.org/content/4/1/011-linux-on-cf.html
External power supplies
Looking around my computer room I see a variety of new and old devices powered by external power supplies.
Old style plug in power supplies use a transformer and turn power into heat even when not connected to a device. The devices have a power switch at the device (if any at all) so the power supply is always connected to AC.
There are several ways to deal with this.
- Plug the devices into a power strip and keep it shut off when not in use.
- Replace the linear supplies with more efficient switchers.
- Replace the devices with ones that use less power.
- Share one efficient supply among several devices.
Canon Scanner has a linear 10V 500 mA supply. I seldom use it so I will put it on a power strip as the first step. (Or leave it unplugged.)
My snazzy Klipsch computer speakers have a large heavy linear supply with weird outputs: +/-18VDC, 834 mA. I can put a switch into its AC power cord pretty easily.
I also have a pair of Yamaha speakers that use a 14 VDC supply; I got them at a thrift store and have always just used a 12V supply with no problems. I might just switch to using them instead of the Klipsch speakers.
My cordless Uniden phone has a small linear wall wart, I think about 9 volts.
I use a separate DTA-310 to convert the Uniden to VOIP. Would replacing the phone with a VOIP phone use less power?
My Toshiba cable modem has a 12 VDC, 1 amp supply. It has to be on all the time so its draw when idle is not as important.
My Linksys BEFSR41 gateway router + 4 port switch has a linear supply. I think I can replace it with a switch on a linear supply and use my Linux system as the firewall. This means finding a switch that draws less power. (I have several in my junk pile.) It also means adding an ethernet port to the Linux system; have to make sure it still uses less power. I think I might try a USB ethernet adapter. I only need 10 MB on that connection so it should be fine.
At our other computer station Bellman I have a Budgetone 101 VOIP phone and a Linksys WiFi router.
