Atom build power consumption?



  • Those of you running pfSense on atom boards, what are you seeing for your power consumption?  I saw one place mention 30W, but that was with ION, so I'm assuming it can get lower.


  • Netgate Administrator

    Is that idle or max?
    My own system draws 22W at the plug after pfSense has booted. It's a Pentium-M 1.7GHz.
    I have spent quite a while tweaking it to get that low.

    To minimise power consumption make sure you get a CPU that has speed step (or equivalent) that is supported by pfSense. For an Atom that means getting a netbook type, NXXX.
    Use an appropriate power supply. A standard 400W atx PSU may will be very inefficient when operating at less that 10% of it's rated output, like maybe <50%!  :o  Using a high efficiency PSU like the PicoPSU (or chinese copy!) will help a lot.

    Steve



  • I've got the D525 supermicro board w/picopsu and a laptop drive.  This is only a rough reading from my UPS, but it shows 30-60 when running and 15-40 when off.  It bounces around because I am also running a mac mini server and a Drobo (idle, but on) off this PSU and couldn't shut those down to check



  • @stephenw10:

    Is that idle or max?
    My own system draws 22W at the plug after pfSense has booted. It's a Pentium-M 1.7GHz.
    I have spent quite a while tweaking it to get that low.

    To minimise power consumption make sure you get a CPU that has speed step (or equivalent) that is supported by pfSense. For an Atom that means getting a netbook type, NXXX.
    Use an appropriate power supply. A standard 400W atx PSU may will be very inefficient when operating at less that 10% of it's rated output, like maybe <50%!  :o  Using a high efficiency PSU like the PicoPSU (or chinese copy!) will help a lot.

    Steve

    Yup.  A lot of people buy into the 80-plus certification without realizing that 80-plus only needs the PSU to obtain 80+% efficiency at 20%, 50% and 100% loading.  Below and in-between, the PSU could function at 10% efficiency and still obtain the certification.

    As for reducing power consumption, I've found the HDD to be the main culprit.  A laptop drive will use less power, a single platter model lesser.  SSDs even less and surprisingly, a thumbdrive would not even touch 0.2W in operation.  Unfortunately, the last option would require the embedded variants and has issues with the USB mounting in FreeBSD 8.X at the moment.

    For the more extreme, there are hardware mods.
    My previous pfSense router is now a partial testbed where I undertook some vmods.  I might reinstate it as a pfSense box again depending on how the National FTTH plans roll out at my place.

    Specifications:
    OS: Windows 7 Professional
    CPU: Intel Conroe-L Celeron 220 @ 1.2GHz
    Mobo: Intel D201GLY2A
    Memory: 1 x 2GB DDR2-800 Kingston ValueRam
    HDD: 160GB Western Digital WD1600-AAJS
    Case: In-win BM-639
    PSU: 120W stock from casing

    Some pictures of the mod:

    And the actual savings:

    You would need to note that I've a full sized desktop harddrive and the PSU is not certified or known to be power efficient in any way.  Also, although this is a mini-ITX board, the CPU is actually a crippled Core 2 Duo and nowhere nearly as low power as the Atom.  However, as it is an out of order execution CPU, it would outrun the Atom 330 dual-cores easily even though it's only a single-core 1.2GHz unit.
    The HDD itself lends about 6W of power consumption at the wall.  I've no doubts that a current generation 2.5" single platter HDD would reduce the power figures by a good 3W -5W easily.



  • @stephenw10:

    Is that idle or max?
    My own system draws 22W at the plug after pfSense has booted. It's a Pentium-M 1.7GHz.
    I have spent quite a while tweaking it to get that low.

    What kind of tweaks did you do to it?  And are you running any of the heavy packages?  I have a 1.6G P4 that I was using.  It sat at 55W, but I'm not sure it'll be enough power to run snort, etc on a faster connection.

    To minimise power consumption make sure you get a CPU that has speed step (or equivalent) that is supported by pfSense. For an Atom that means getting a netbook type, NXXX.

    There are processors without speed step?  I didn't think any existed anymore.

    Use an appropriate power supply. A standard 400W atx PSU may will be very inefficient when operating at less that 10% of it's rated output, like maybe <50%!  :o  Using a high efficiency PSU like the PicoPSU (or chinese copy!) will help a lot.

    Steve

    I'm using whatever came with the machine, currently.  I've mostly been using Dell machines that I had sitting around.  So not sure what the PSU rating on those is.  I'll have to look at getting a lower rated power supply.

    I'm still not sure what the deal is with PSU wattage, though.  My GTX275 requires a 550W(I think) PSU, but the system only pulls around  200W from the wall.

    The pics aren't loading for me.  I'll have to look at them later.


  • Netgate Administrator

    @Bai:

    What kind of tweaks did you do to it?  And are you running any of the heavy packages?  I have a 1.6G P4 that I was using.  It sat at 55W, but I'm not sure it'll be enough power to run snort, etc on a faster connection.

    I replaced the cpu with one that had EIST and enabled powerd. I replaced the PSU with with a DC-DC type. I adjusted the cooling fans to more appropriate speed for the new power consumption.

    There are processors without speed step?  I didn't think any existed anymore.

    I know, shocker! It's true though that the desktop Atoms don't. All the best power reducing technologies are used on mobile cpus as battery life is so important.

    I'm using whatever came with the machine, currently.  I've mostly been using Dell machines that I had sitting around.  So not sure what the PSU rating on those is.  I'll have to look at getting a lower rated power supply.

    I'm still not sure what the deal is with PSU wattage, though.  My GTX275 requires a 550W(I think) PSU, but the system only pulls around  200W from the wall.

    PSU manufacturers like to write big numbers on the side of their boxes! In reality I doubt that psu could sustain 550W output but it has to able to handle large peak output if everything comes on at once.

    Steve


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