Hello!

I'm planning to build a small home router/server - replacement for my current wrt54gl. I want to keep it running 24/7 so i need power consumption to be as low as possible. I did some energy calculations and i decided to not use more than 25W, where 5W of it i reserved for gigabit switch to improve data transfer between single computers.

Next thing to think about was base platform. Firstly i was thinking about something similar to raspberry pi but with two ethernet ports. Instead i have found ALIX board based on AMD geode processor - what made me happy because i like AMD products (all home computers are based on AMD hardware ). When i was thinking more and more i asked myself - if i have an x86 platform - why not to go further and use something faster. Idea to use mini-itx motherboard with integrated E450 was born. First problem which i faced, is that in my country i cannot buy motherboard with E450 equipped with 2 ethernet ports I thought then about Intel processors, much more energy efficient. I have found an Intel DQ77KB motherboard and i3 3220T processor.

So, here comes most important question: Since server will be running most time idle, is it possible to achieve in idle less than 20, or better 15 Watts on Intel platform? i3 has TDP 35W - i dont know how much energy it actually uses.

Cant decide between ALIX and Intel platforms. I know that, with alix i will have 2 or 3 times lower power consumption than on Intel platform, but the second one gives me a lot more possibilities "what to do with it". Its impossible to me to calc how much energy intel platform can use - or if exist some better alternative. Anybody can give me some suggestions?

i3 CPUs are overpriced and useless for your application. You should be able to use a fairly cheap Celeron dual core with that board.
It's definitely possible to idle at 15W with modern Intel boards but you need a very efficient PSU. The board you selected is not the most efficient but I think it includes an efficient DC PSU which means you won't have to source a pico or equivalent. To reach the desired idle power consumption with that board, I think you'll have to be careful to select a very efficient AC/DC brick and fiddle with BIOS and software settings (so as to make sure the GPU doesn't waste power for instance).

Another less expensive possibility is Intel's Atom dual-NIC board. Even that CPU is way overkill for your application. It lacks the VM extension however. And the board doesn't pack a DC PSU which means you'll need to source an efficient PSU. And the board isn't very efficient to begin with. But it's cheaper which would save you more than a couple of watts.

You'd save power by using a single NIC, first because PC NICs consume power and also because the most power-efficient boards such as the DN2800MT or the one in the NUC have a single NIC.

DQ77KB is what I thought of when I read the topic. Glad you came to the same conclusion. I'd like to second what HFat says; no need for an expensive i3 part, certainly not a factory underclocked T version. Get a cheap dual core Sandy Bridge/Ivy Bridge, Celeron G530 or better. Don't bother so much about TDP as they are all very power efficient.

A switch can draw less than 1W. My TPLink TL-SG1005D is 0.72W "idle" and my Netgear GS108 is a whoppin' 1.4W.

Shouldn't the board support the Ivy Bridge Celerons? Last time I checked, they were almost as cheap. And they *should* be more efficient. But maybe they're not... the CPU part is almost certainly more efficient but I'm not sure about the integrated GPU.

True. Ivy Bridge would be better, edited my post above.

Thank you very much for the answers.

Processor. I dont know very well Intel processors, so i3 was my first shot. Atom is not an option for me, because i want to build this with some possibilities to upgrade in future. Now i'm thinking about Pentium G2020(T) - Whats difference between version with and without T? Its just lower clock or some more improvements?

I have an unused power brick from a HP Probook laptop (19V, 60W) - i wonder if it will be enough to use? In spcr review of dq77kb with Pentium G2120 tests shows 41W in full CPU load - so i think i have right power supply.

I will install also an wifi card - dont know how much power it can draw.

The brick isn't powerful enough in theory but I bet it will be enough in practice. Even if it wasn't, you could underclock. But if you want to be safe in theory, get a *T CPU. The difference is stock overcloking and stock undervolting, plus maybe something on the GPU side. The Sandy Bridge dual-core *T CPUs weren't worth the money and I bet the Ivy Bridge aren't either. But if you can get them for 5$ more or something and you really want to be safe with your 60W...
The Pentium would be a waste however. Get a Celeron. The cheapest dual-core is ridiculously overkill already. ANY modern x86 would be ridiculously overkill. The only point in paying more than the cheapest part is efficiency and features (like the VM extension the Atoms don't have).
Other than efficiency, there is no conceivable reason to ever upgrade a home router by the way.

Note that your laptop brick is probably not the most efficient. I doubt you'll get 15W with it. You usually have to purchase very efficient bricks because only the most modern devices sometimes come with efficient bricks.
But maybe HP wanted to be "green" and spent money on an efficient brick. Does it have any efficency-related markings (there are efficiency standards for bricks with labels)?

Look for "Efficiency Level" on the brick.

I have a few 19V HP bricks I've found in the dumpster, usually with damaged cables but otherwise fine. They are rated IV and some are even rated V.

You will probably be able to underclock with that Intel board, but not undervolt. A *T CPU would be ideal, but they are usually not worth the extra money. I got my i3 2100T actually because I wanted to use a 60W brick, and knew manual undervolting wasn't an option. Luckily I got it cheap.
Unless you start adding lots of 3.5" HDDs you will be fine with a 60W brick, even with a non-T CPU.

I've got a laptop brick rated V... but that laptop is still under warranty. I'm still using a C2D laptop which came with a III brick. I'm surprised you found several V-rated bricks in a dumpster!
These ratings are of limited use to guess at actual efficiency but it's so easy to read the rating compared with efficency testing!

In theory, Intel sells the cheapest Celeron *T CPU at the same price as the cheapest regular model actually. If you don't care for performance (and you don't for this application) you might as well get a *T... in theory. Nobody even lists the cheapest *T models here.

If your initial use case is just a router, you can do that easily with a newer dd-wrt compatible unit, plus it will include wifi and 4 or so gig ports, and run on a couple of watts from a reasonably efficient 12v wall wart. It will be difficult if not impossible to get these things separately for less money or less power usage.

Once you remove the router part from the server, things get a little easier. However, you didn't mention what you would use this server for, so there is really nothing to base a recommendation on.

I can use also 90W brick, both of them has rate V. Price difference between Pentium G2020 and Celeron G1610 is ~15$ in my local shop - i decide on it later, and just stopped thinking about an *T models - they are available but i need to wait more than month, where non T models are available within an hour.

I know, that just for router even a celeron is to "big", but it will work as just router only at first weeks until i configure routing, port forwarding, wifi and other router-stuff with security testing of system (which will be debian or gentoo). Later on, i will expand it for sure by an traffic statistics applications and MySQL (or postgresql) database for data storage. Other tools includes windows domain server (as i found somewhere article about running it on linux based computer), file server for home storage (both samba and ftp), apache with php to run my own application managing internal network and at last an virtual machine (or maybe two) running windows xp (probably). So it will be quite a lot of stuff when i finish all work - of course its not possible to achieve it ALIX board, with atom it may be a little bit slow so thats why i want to stay on Celeron/Pentium and have a possibility to expand in future.

And yes, i know that with all of this stuff machine will consume more than 20 watts when used but its not a big problem - still less than having normal router and separate PC as a server. I want to achieve low power consumption mostly on first 2 - 3 months of running it to get know about costs of having machine running 24/7 and later on think i will be cool to spend lot of time on many software configuration just to get even a 0.1W less

I run this type of stuff on Atom and the AMD equivalent (except I don't run Windows which is pointlessly cumbersome and expensive for this type of application). As long as you're talking about home stuff and not about serving dozens of concurrent users or something, a modern Celeron would be ridiculously overkill.
I'm not saying you shouldn't buy one of these Celerons. They're great value but the reason to buy them for your application is not performance but the combination of I/O, features (both lacking on Atom boards) and efficiency (lacking on AMD's side, except perhaps when it comes to stuff like the C60M1-I for which I've never seen a reliable measurement).


Not necessarily. It will probably depend on details like brick efficency, RAM, storage and whatnot.

You're right in some way, but at this moment i cant find any mini-itx atom (or amd) board with two ethernet ports. Many of them are equipped with wifi cards or bluetooth, but not 2 ethernets Dont mean that those boards are temporarily unavailable but shops does not even have any in offer

If nothing change in this matter until next month (when i want to start buying components) i will stay with celeron option.

I don't know where you are located, but NewEgg has a few such boards:

http://www.newegg.com/Product/ProductLi ... edSearch=1

Is there a reason why do you require dual ethernet on board instead of putting one ethernet port on an addon board ? For example MSI C847MS-E33 is a mATX board with just one ethernet, but you can put an addon ethernet card there and voila - you have a low power dual core 1.1GHz Celeron, cooled passively, for 70€ or something like that.

D2500CCE
It's not one of the best boards however. The only reasons to get it would be the price and that it's fanless. But it's got real disadvantages aside from performance.

Requirement to have two ethernets on board came from size of nice case which i already have and want to use - only miniITX boards (and smaller) fits. If i use pci(e) slot with second ethernet controller i have no more slots to connect wifi card

D2500CCE could be a option, but what are it disadvantages? As i can see from first (quick) look at specifications it lacks USB3 - not big deal, but it may be useful (i have 3 external hdds with usb3). Two com ports are more + than - for me and picoPSU is needed.

You could use a USB or mPCIe wireless NIC.
If you can live with a pico and dual-NIC PCIe card (I thought there was no room for a card in your case), the C60M1-I might be an interesting option. The PCIe card would burn some power but you'd avoid the Atom limitations while keeping your build cheap and fanless.

External drives can be hooked up to an internal SATA port. There are SATA to eSATA cables or brackets that make it convenient. It may not be the safest thing to do and some boards might not support hotplugging so you're on your own if you want to try it. All I can tell you is that I've done it a few times.

The problems with the D2500CCE? It's not the fastest or the most efficient Atom. And it's not cheap either.
On top of the problems most Atoms boards have (limited I/O, no VM extension), this generation of Atoms has driver issues with their integrated GPU because Intel outsourced it to PowerVR and didn't do much to support it (it was really made for Windows tablets/phones). Then again, the driver issue is not much of a problem for a headless server (the only problem is stopping it from wasting power) and the NICs look nice.

In that case GIGABYTE GA-C847N-D. Same 1.1GHz CPU with 17W TDP, 2 x Realtek GbE LAN, but it has only PCI instead PCIe.

Pretty much this. The GPU on that board is just insane (in a bad way). I bought it to run a pfSense firewall/router because of the dual Intel NICs, and the display barely even works in text mode, which is still an issue if you ever have to troubleshoot a headless server. For example you can't use the 64-bit build of pfSense, otherwise the display is garbled for some reason. The driver situation *might* be better now that Win8 tablets have started to show up using this GPU, but for a while you couldn't even get decent Windows driver support, let alone Linux or FreeBSD/pfSense. The main reason to get it over, e.g. a Supermicro dual-Intel-NIC Atom board is that it's about half the price and probably lower power, but the Supermicro does have an IPMI controller which is very nice for remote administration.

I agree that the low-end Sandies and Ivies have really good idle power these days. I haven't measured my D2500CCE lately but I don't think it was much lower than 15W anyway.

I do not recall having any issue with Debian.


BSD's hardware support isn't the same as Linux's.
Linux had people working on the driver from the beginning but older versions of Linux worked fine in text mode anyway. I would have thought that text mode would work on any GPU without a specific driver. But perhaps I somehow benefitted from work that had been done on older, less common versions of this GPU.

Tank you for all your answers.

Right now i have 2 almost complete sets, "rich" and "cheap"

"Rich" one:
CPU: Intel CELERON G1610
CPU Cooler: Intel BXHTS1155LP
MB: Intel DQ77KB
RAM: 2x 2GB 1333
HDD1: Crucial SSD M4 32GB mSATA (system)
HDD2: WD Scorpio Blue, 2.5'', 500GB (storage)
CASE: Lian LI PC-Q05 Black (already owned)
+ wifi card

"Cheap" one:
CPU + MB: GIGABYTE GA-C847N-D
RAM: 2x 2GB 1333
HDD2: WD Scorpio Blue, 2.5'', 500GB (storage)
CASE: dont know yet
+ pci wifi card

Second one is half (or less) price of first one I want of course first one, mostly because it will fit to my cool case and i just like it more

Thank you again for help, now i have clear vision what to buy and why. I will edit that post later when finally decide which one to buy.