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Reducing power consumption with pfsense router converted from old laptop?

Discussion in 'Routers' started by SmallWalrus, Jun 25, 2011.

  1. SmallWalrus

    SmallWalrus New Around Here

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    Jun 25, 2011
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    I've recently turned an old X61s into a pfSense router, and it works *great* except one thing that bothers me is that it pulls around 20W through the wattmeter even though it's only running at 400mhz (according to the FreeBSD console).

    I've actually tried connecting a headless X61s to the same AC adapter and I got the same readout, so I am starting to suspect that...
    1) the monitor uses that little power
    2) the AC adapter is not that efficient and uses that much power no matter what

    Has anyone else had a similar experience in using old Thinkpads as routers? What do you do to keep the cents down on your power bill?
     
  2. YeOldeStonecat

    YeOldeStonecat Very Senior Member

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    May 31, 2008
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    Yeah I used to use old Thinkpads as PFSense routers for years....going back to T2x models...as Thinkpads use good onboard hardware that is well supported.

    They don't take up much space, low noise, low heat, built in keyboard and monitor, and a built in battery backup! All good stuff.

    As for measuring the power consumption...never bothered, it was leaps and bounds better than the full sized x86 towers I used to run it on.

    I've since moved to a Supermicro 1U appliance I built..with an Atom D510.
     
  3. GregN

    GregN Senior Member

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    Feb 3, 2011
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    A not serious response

    I don't know where you are located, but taking the US national average of about nine cents per kilowatt hour, and your stated 20W consumption rate, your PFSense router, running 7/24 is costing you less than two dollars a month [ (24*30*20)/1000 *.09 ]

    Here are some suggestions for further reducing that cost:

    1. Replace the ThinkPad with a netbook (you might save 2 bits).

    2. Don't run anything on PFSense that requires SPI ( Snort, SquidGuard, etc )

    3. Remove the battery from the laptop ( not positive this will help, but it can't hurt )

    4. Disable wireless and/or bluetooth on router

    5. Turn off the router when you go to bed

    6. Run a covert extension cord from your neighbor

    7. Move to North Dakota ( supposedly cheapest power in the country ( <7c ), though your heating bill... Tennessee is a close second )

    8. Replace your power cord with one with silver or gold wires, reducing overall resistance ( for that matter, maybe the entire house wiring )

    9. Lean the router below the power socket, gravity might help.

    10. Pack the laptop in a dry ice sleeve, or some other cooling medium (LN2, LOX, LHE )


    I think I read somewhere that a guy had gone completely green, off the grid. Problem was that the price of ice for food storage, and the cost of batteries for his nightvision goggles was killing him....
     
    Last edited: Jun 26, 2011
  4. SmallWalrus

    SmallWalrus New Around Here

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    Is power really that cheap in the States? Here in Singapore it costs 25 cents local currency, which is somewhat close to 20 cents in American dollars.

    That's quite a bit more unfortunately, hence the desire to chop every watt off when possible, considering this pfSense box will be joined besides a QNAP Nas, a Windows home server, and some optical network terminal and another ISP supplied router that we just got to use :D
     
  5. Dennis Wood

    Dennis Wood Senior Member

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    Two things that you should look at:

    1. In pfSense enable PowerD (System, Advanced, Miscellaneous). On the Jetway NC92-330 systems (dual core Atom at 1.6GHz) I just built, the pfSense dashboard is often reporting the CPU at a much lower clock-rate when not needed. With the CPU consuming only 4 watts at full pop, this setup doesn't use much power.

    From pfSense GUI:
    "The powerd utility monitors the system state and sets various power control options accordingly. It offers three modes (maximum, minimum, and adaptive) that can be individually selected while on AC power or batteries. The modes maximum, minimum, and adaptive may be abbreviated max, min, adp. Maximum mode chooses the highest performance values. Minimum mode selects the lowest performance values to get the most power savings. Adaptive mode attempts to strike a balance by degrading performance when the system appears idle and increasing it when the system is busy. It offers a good balance between a small performance loss for greatly increased power savings. The default mode for pfSense is adaptive."

    2. In your laptop BIOS, browse everything and make sure your CPU power options etc are set as aggressively as possible.

    3. Assuming the monitor on your laptop is staying on, turn brightness down to zero when you don't need to view.

    Be curious to see if this makes any difference.
     
    Last edited: Jun 26, 2011
  6. GregN

    GregN Senior Member

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    In Singapore... guess that eliminates the North Dakota option.

    Not sure which version of PFSense you are running, PowerD is in the 2.0 release candidates.

    I'm running a Atom D525 in Cerberus, and my power consumption varies between 20 and 25W, but I make heavy use of SPI.

    Is there such a thing as a high efficiency power brick?
     
  7. Dennis Wood

    Dennis Wood Senior Member

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    Apparently the Jetway NC92-330 with the minifox PSU combination is a bit hungry. 30 watts idle, 32 watts busy using a 40GB SSD. The minibox brick and "Pico-PSU" cannot be too efficient.
     
  8. SmallWalrus

    SmallWalrus New Around Here

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    Jun 25, 2011
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    1. Yeap, I have turned on PowerD as well, and on the main page the CPU is often running at a speed like 400mhz (usually it goes at 1.6ghz), so it seems to be working good.

    2. Done that too :(

    3. This laptop doesn't even have a monitor, it is a headless machine.

    The funny thing is I tried comparing pfsense running on this particular laptop and another one (with monitor, etc etc) and they both measure the same wattage from the wattmeter. Something seriously doesn't add up, where is that extra juice going?
     
  9. SmallWalrus

    SmallWalrus New Around Here

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    Yes, I am rather suspicious of the power brick as well. How is your CPU throttling looking?
     
  10. GregN

    GregN Senior Member

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    CPU throttling? I'm running V1.23 until the Snort and Load Balancing issues that Dennis Reports are resolved.
     
    Last edited: Jun 27, 2011

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