ASUS M4A78LT-M LE
Sempron 140
Antec 380d
Mushkin Enhanced Silverline DDR3 1333 1x2GB
Samsung F3 1tb
Rosewill Blackbone case

That is what I currently have. I am looking for suggestions on ways to par down the power consumption. Eventually I plan to add a 2tb Samsung F4, but probably not for a few more months.

Current power consumption is 49w sitting in the BIOS (I don't know what booted consumption would be, as I am waiting for a USB thumb drive to arrive by lovely USPS sometime in the next couple of days so that I can load Ubuntu 10.10 to the machine).

My goal is to get idle power consumption under 40w and loaded power consumption under 50w (or at least file serving power consumption under 50w). Ideally I'd love to get idle power consumption with the disks spun down under 30w, but I don't know if that is achievable.

Advice on a starting place? I've already disabled the com and parallel ports in the BIOS. Not sure what else I can pare down and I am also looking for suggestions on a starting place and/or target for various BIOS voltage settings. I don't mind underclocking some as this machine is only going to be used as a file server in a 2 user environment.

I am considering dropping a Vertex 30GB in to the machine is a boot drive to see if that might add some performance as a file server (I am skeptical that it will with the usage scenario I am expecting). I'll probably play around with that as on a whim I bought one off Ebay for cheap about a week ago. Otherwise the SSD is going in my PC as an app disk to complement the 60GB vertex I have in there right now (500GB F3 main spinning disk, 2tb F4 bulk storage).

Thanks!

BIOS power draw is not a good judge of system performance. I'd get a power meter instead. Preferably one that goes between the PSU and the motherboard like Zalman's power meters, one that goes between the PSU and the wall will probably be cheaper, but won't compensate for AC/DC conversion loss.

You can disable the PCI and PCI express slots if you're not using them.

Underclocking the processor isn't a big factor if cool 'n quiet is enabled, as that adjusts the speed according to system demand. What I would do instead to conserve is lower how fast it can go when demand rises by lowering its maximum multiplier below the stock setting of 13.5. If your motherboard supports it you can try unlocking the second core in the Sempron to turn it into an Athlon II X2 4400e. (That may use a bit more power but it will perform faster to conserve in the long run.)

Booting from a SSD will definitely save power as only one disk will need to rotate. And separating system reads/writes from storage read/writes onto separate disks will improve task speeds. Furthermore you can adjust your computer's power settings to turn the hard drives off after they've been idle for a time. When needed they will spin up again.

Err, sorry. I am using a Kill-a-watt. The power draw was when in the BIOS, since I don't have an OS loaded yet to see what the power draw is idling on the desktop/console. I care more about final plug draw than DC draw really.

Thanks for the suggestion on the PCI-PCI-e as I'll probably never use the PCI slots and for now no reason to use the PCI-e slots until I need a Raid card or another GbE NIC.

Sounds like I should give the SSD a shot.

For disk spin down, I have it set at 8 minutes on my PC, I am thinking 5 minutes might be okay on the file server and go from there.

I'll try unlocking the core and see what that gets me between reducing the multiplier and voltage as well as what task times are like.

Maybe you can reach your target with a more efficient PSU. In order to be able to use an efficient PSU without spending too much, you might have to underclock.

But the most effective way to lower your power consumption is to buy a low-power board. That's probably not what you wanted to hear but there you are. Suitable Atom boards start at about $70 new. With a reasonably efficient power supply, your PC should draw less than 25W at idle. There are other options with more features and/or lower power consumption if you're willing to spend more.
If you want really low power consumption, consider getting an ARM NAS instead of using a PC. You can sometimes find one for very little money on the used market. You can install your own software on some of them.

It would be a waste to use a SSD to boot a file server unless you want fast cold boots for some reason. Even a USB drive might be a waste.


Since the OP is not using Windows and has 2G of RAM, she can get the same result by booting off the hard drive.
And there's no reason you should have a significant amount of system read/writes once the system is booted. So there would be no performance benefit. If there was any, you'd get an even better result by loading everything in RAM at boot anyway.

Running from a Live CD might be even better. If the configuration is saved on a floppy or ZIP disk, neither drive will draw power between login and the shutdown commands.

Good ideas, especially vis a vie the SSD.

I knew it was going to be a bit of a trade off going with a uATX board over an Atom uITX board. However, I wanted something with at least 6 SATA ports as well as more than a single PCI-e slot for future expansion. Eventually I may be adding a GbE NIC and do two bonded connections for more through put speed and I wanted to leave room for a RAID card at some point. I also wanted something with integrated graphics and integrated RAID support (few Atom boards have on board RAID and I haven't see any that have more than 4 SATA ports or a single 16x PCI-e slot).

For the PSU, about the only way to go more efficient at low draws is a PICO, and the cost would be significantly more. The Antec 380d is about 75% efficient at a 25w draw and close to 80% at 50% draw. One of the best for low power draws (other than a PICO, which would have been about $60 more for everything, and limited again on the number of SATA devices without a lot of daisy chaining).

So the setup I have is what I need for future expandability and price, I am just looking for ways to maximize the efficiency of what I have. I knew going in it would be no 10w champion.

At some point I do plan on an ARM NAS to add to my network for ultra low power media streaming, but it isn't going to come close to slicing my bread for what I need for file serving and backup duties (and I may do web serving off the box at some point as well).

Thanks.

There are other options than cheap Atom boards (Atom and otherwise - based on the rest of your post, you haven't seen all low-power options)... but they're not as cheap. Your mainstream board makes more sense in that perspective. It's not low-power but it's not always rational to pay more to get low-power parts.


Virutally everything has integrated graphics nowadays.
Why do you want integrated RAID if you're not going to run Windows? I don't get it.


75% at 25W is pretty bad. It's not that hard to do better.
But you may be right in that it's probably not worth the cost (you might as well buy a low-power board instead).


You may not be aware of what ARM can do nowadays. ARM can definitely pull off fast file serving, a little web serving and mundane backups. But the cheapest ARMs are not that good. So once again, a watt-guzzler may be cheaper for what you want to do.

That is unfortunately what I have concluded. My whole budget was sub $300 for everything from CPU to drive to case. So I could have gone lower power, but it would have cost significantly more, or it would have compromised on what I need/want.

For why do I want RAID support, because I want chipset native RAID 0, 1 and 1+0 options instead of just through the OS. Its more power and processor efficient instead of putting the load on the CPU and the OS to handle RAID.

ARM can handle most things, but not cheaply and there isn't very good ARM support on OSes. Community support for distros of Linux that support ARM is a heck of a lot more lacking than for x86 and tend to be a couple of major releases behind in terms of features. Also I'd be limiting myself in terms of hardware expandibility in the future, just like I would be with most/all Atom uITX boards out there right now.

Really my only option is optimize what I have. A future build, maybe 2 or 3 (or 4 or 5) years from now that might well be a different story, but for today I am limited to a Sempron 140, uATX board and Antec 380d as the basics of the system.

On a completely side note, I finished wiring my main level with Cat5e back to my basement storage room where I am going to hook-up the file server and I have an 8 port GbE switch located (sadly running a 20ft extension cord to the otherside of the storage room to an outlet there. I ran the wire and installed the box for a new outlet since there are none on that side of the storage room...but I realized I didn't have any outlets laying around! I have about half a dozen mains switches, but not outlets...GRRR!). Connected my computer up to one of the Cat5e outlets...and it would fail to boot. Disconnect and fine. Did that twice in 30 minutes. Removed my wireless USB adapter, works fine now. I wonder if maybe I had knocked the wireless USB adapter lose as it is next to the ethernet port on the MoBo and some kind of partial pin connection was causing the MoBo to freak out on power on.

I urge you to reconsider then. Integrated RAID is generally not recommended. It has reliability and flexibility issues.

Do you know what the load you're afraid of is exactly? Maybe I'm looking at the right thing because I don't even notice it.

Any chipset RAID is going to be using the CPU anyway, so you gain nothing. All a chipset or "fakeRAID" controller does is have a BIOS/Driver combination that does the RAID processing on the host CPU. They don't have any processing power of their own. Since you are not using Windows, there is a good chance it won't be supported by your OS anyway.

As hfat said, there are reliability and flexibility issues for using FakeRAID. If your MB/RAID controller dies then you have to get another one of the same type to get your data. With software RAID then all you need is another MB with enough SATA ports, any would do.

Besides, if you are only doing RAID 0, 1 or a combination then the processing overhead is so minute as to be ignorable. RAID 5 takes a bit of calculation, but still nothing for a modern CPU.

this is not my experience. Ubuntu and Debian support ARM architecture (v7 and v5 respectively, with v7 coming to Debian too). I haven't run into any package for my ARM NAS that is not available for Debian armel (the Debian name for ARMv5 EABI arch) while being available for x86. Further more, the arm packages are compiled from the same source version, so they're not lagging either.

You need to get it booted into an OS with power saving features enabled, and look at your killawatt. You might be pleasantly suprised.