I'm looking for ideas for energy efficient PC that I can throw into the bowels of my automation closet, never to be seen again.
Device will run few apps such as:
- UniFi server for my house (possibly few other sites if my house runs well)
- Access Controller logger (low CPU usage)
- whatever else I can come up with in the future

I do not need this to be any kind of backup repository or file server (traditional NAS).
I'm speculating that 250-500Gb 5400 SATA would suffice.
Depending on ROI, I may go the SSD route.

I have spare monitor/keyboard/mouse for initial setup; afterwards, it will be 24/7 headless unit.

This is in my own house, and I guess I could use any of the following:
- old laptop (that way I'll never need to haul monitor/keyboard if recovery/troubleshooting is needed)
- Rack mounted server (never used them; don't know anything about spec'n one)
- small form factor PC [Link: amazon.com]
- regular, old PC (concern about power usage if I had something laying around with 350-600W power supply)
- other. Anything else you guys can think of.

I never played with anything other than PC, so AppleTV and Linux type devices are out of question.

Gime some links from eBay/Amazon if you purchased something recently that you think would work for me.

I have a never-booted, factory fresh life|ware HTPC I'll sell u cheap...it'd be perfect!

I wanted to be a life ware dealer so bad

Your ROI will be zero unless you can get the thing to print money.

Re-read my ROI sentence, this time pay attention to its context.
ROI when using SSD has to do with performance and power savings vs. the initial SSD price premium and the fact that most PC boxes still ship with spinning HD.
But I suspect that you already knew that.

Do me a favor Ernie; unless you have advice with part numbers or URLs, and first hand experience; ignore this thread.

What are we talking about spec wise and price point?
Aren't those boxes usually high end with high power PS in them? I need something that will run 24/7 and not heat up the house.

Xi3 has some interesting models.

How about an Intel Next Unit of Computing... Intel NUC?

This model might be a nice choice for you:
[Link: newegg.com]

This has a 4th Gen Core i3 processor (since you're interested in power efficiency, I suggest staying with 4th gen or later). It supports a 2.5" SATA 6GB/s drive, either rotating or SSD, as well as Mobile SATA PCIe. It comes without memory, drive, or OS, so you get to choose those yourself. It supports gigabit ethernet, and is only 4.6" x 4.4" x 1.36", and if I remember right they come with a VESA mount, if you decide you need that later.

At $270, I think it's a great bargain, for an i3 processor, motherboard, power supply and case, in a small form factor package. Add $80 for 8GB of DDR3 1600, $74 for an mSATA 120GB Drive. If you want 802.11AC, for only $32, it is easily added and the antennas are situated already within the case.

For your purpose, the $270 NUC + $80 8GB + $74 120GB gets you what you asked for, at only $424. I think that's a bargain. This box is also capable of more, if you decide to use it with a display later. This processor has a TDP of only 15W, so this processor will only consume 15W running full out. Of course total consumption will depend on what peripherals you attach as well, but I'd expect idle currents for the total system at about 10-12W, which is pretty low.

^^ good find.

Thanks man; exactly the information, suggestion and details I was looking for.
Looks like I could save another 5% here: [Link: amazon.com]

Today, I found an older 15" HP laptop that we haven't used in about a year.

Does anyone know of app that can stress PC so that I can plug it into WattKiller and run it for 10-24 hours to see how much power it'll use?

If it uses too much power, I'll go the NUC route for sure.

Look at a company named Logic Systems. They specialize in rack mount PCs of all sizes and powers. I have several of their units in my home's rack. What I like about them is they are extremely reliable and several of mine have been running for years non-stop except when I physically stop them for maintenance or software changes.

I know you said you want energy efficient, and you also said no mac based products. However i dont think you will be able to find a Energy efficient PC at a decent price point, especially one that can match the efficiency of a mac mini.

Why not just get a mini and throw windows on it? in the long run I think you will be further ahead cost wise and efficiency wise.

[Link: apple.com]

Small rack-mount servers (1U-2U) are usually extremely loud. The fans are small, high RPM units that approximate the sound of an F-16 in flight. If your rack is within earshot, you'll probably need to be in the 4-5U range to get fans with large enough diameters to be on the lower end of the dB meter.

And they are generally substantially more expensive than an off-the-shelf consumer PC. You can probably get a PC and a MA custom rack shelf for less than a 1U rack mount.

You know, there's some real cheap, new, laptops with that same processor in them plus memory, etc for around that same money (total). For your use that might make a nice sized small package plus with the keyboard and monitor in the 'package' it would make it easy to do software upgrades on it when necessary, it would be easy to pull it out of the closet and plug it into the network on the desk, and update it.