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15w green htpc

8K views 16 replies 12 participants last post by  tman247 
#1 ·
Between th 25w corei5-661 pc tom's hardware built and the 11w mac mini (c2d), I figured there had to be some middle ground. So I ran into a site which has multiple builds using about 15w.

Link to various builds and pics Translated from German (compilation thanks to OP Herb Master)


Sample build (OP rakim):


H55M 1 x MSI-ED55

1 x i3-530

1 x G. Skill DIMM Kit 4GB PC3 ECO-10667U CL7-7-7-21 (DDR3-1333) (F3-10666CL7D 4GBECO)

1 x yellow picoPSU-120 with Morex PSU PJF80-PSADP

1 x Thermalright AXP-140 (without its own fans)

2 x Noise Blocker MF12-S1 @ ~ 400 rpm

1 x Intel X25-M as a system disk

3 x WD BEVT (2.5 "HDD, 1 x 500 GB, 2x 640 GB)

3 x Scythe Quiet Drive for 2.5 "plates


Some comparisions (OP 24shorty):
PSU:


H55 Motherboards:



The tables only appear to go down to about 19w on idle for a full system w/picopsu, though. What is interesting is how much of a difference the picopsu makes in (19.2w vs 27.3w for antec earthwatts). Additionaly as you can see from the table above the mb also makes a difference (19w for msi to 25.5w for biostar). Similarly, the ram (1.35 vs 1.5v) can make a difference but probably not quite as significant as the mb and the psu. I'll add the link for memory comparison as well when I dig that up. Going to the green HDD also saves a couple of watts. I imagine most will have one ssd for os, but if you're building a nas+htpc something to consider that even 5w/hdd x5hdd = 25w in saving.


I'm hoping by the time sandy bridge comes out later this year/early next year, we should be able to see more energy savings. Having comparison like the poster did above is excellent. Just wish more mainstream hardware review sites did something like this - would help us pick the right parts for our next htpc. Now on the flip side, when you're down to
 
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#3 ·
So the key points in lowering power consumption are:


- Use a MSI or Intel (or GIGABYTE non-USB3) H55/H57 mb: up to -10W (compared with other mb)

- Use G.SKILL ECO 1.35V memory modules: -2W (idle) ~ -5W (memory load) (compared with 1.65V)

- Use a 2.5" notebook HDD or SSD: -5W (compared with a 3.5" HDD)

- Use a PSU that is efficient at $55: -4W (84% efficiency at 40W DC draw [e.g. BD DXVA playback] @120V, compared with a PSU with 78% efficiency [MODU82+])

- Total: -21W (saving, compared with a typical H55 system)


This is doable without increasing the cost much. Caveats are


- There is no MSI mini-ITX (if you prefer mini-ITX).

- A 2.5" HDD is pricier and slower. A SSD is much pricier (faster of course).

- picoPSU-120 + 102W Adapter Power Kit can't handle more than 102W DC draw. Actually this is not an issue unless you add a discrete graphics card (HD 5450/5570 are still OK).
 
#10 ·
For my HTPC, I used the lowest voltage RAM + SSD and Core i3 and H57 with onboard graphics and is completely passive cooled with a custom heatpipe solution. (temps are 33c idle, 42c "htpc load", 76-80F ambient temperature).


After setting to power saving mode in Windows and a little more optimizations, I was able to measure 16-20watts idle with a Kil-A-Watt meter. At "HTPC load" (watching movie, tv, music, or surfing the web) was 26-30 watts.


It is set to go to sleep after 30 mins of idle.
 
#11 ·

Quote:
Originally Posted by SlackerX /forum/post/19285092


I'm bringing up this old thread again just to add that one could use one of the new Seasonic 80+ Gold power supplies rather than a pico-psu if concerned about total watts supported. They are ultra efficient and the 400W model is fanless and runs cool.

Seasonic X Series SS-400FL Active PFC 400w Review (efficiency chart) @ SilentPCReview.com

Seasonic 80+ Gold PSUs @ Newegg.com

You can, but it appears to be about $100 more than the picoPSU.
 
#12 ·

Quote:
Originally Posted by rogo /forum/post/19287005


You can, but it appears to be about $100 more than the picoPSU.

Ahh... no. You also need a power adapter with a pico psu. That usually brings the price up to at least $70-100. The SS-400FL costs $139 and the SS-560KM costs $129, with no need for any extras. They are also modular with plenty of power connections for various types of devices. If you can show me a viable pico psu (regardless of the wattage) that costs only $29-39.00, including the power adapter, I'd love to see that...
 
#14 ·

Quote:
Originally Posted by rogo /forum/post/19289205


Ah, no, the picoPSU with the 102w is $70...

http://www.mini-box.com/picoPSU-150-XT-102-power-kit


And the Seasonic is still $140...


So it's "only" twice as expensive, sorry.

That's true. But, hmm... I think that I already said exactly that somewhere... The point is that it is not "$100 more than the picoPSU" as the poster above had stated. That's clear in the links that I myself provided--if you understand that you need a power adapter as well as a picoPSU, which is a fact that many people that may be trying to follow this thread don't know. Just as they may not be aware that there will likely not be enough power connectors attached the the picoPSU for all of their devices, etc.


The picoPSU is an ecxellent product for power efficiency, but there are some limitations. If you need more power than the pico can provide, yet still want to keep the efficiency levels high at idle and load wattages, then these new Seasonic power supplies are an excellent choice that people should be aware of in case they need a bit more flexibility for their purposes--such as adding a few more drives for storage, or a dedicated graphics card for better video processing performance or gaming. As stated here , that was the point of my post in the first place. I believe in getting the most efficient power supply you can to keep any type of HTPC (or any PC for that matter) installation as green as possible. More choices and flexibility equal more low-power PCs.


My own HTPC build is almost exactly like ymarker's sample build in the original post . Even down to the G.Skill ECO RAM and SSD boot/OS drive. My differences are an MSI H57 board, the addition of a blu ray burner, a recent upgrade to two Samsung 2TB F4 drives for storage and an Nvidia GTX 460 for gaming since I don't own a PS3 or an Xbox 360 (both of which are loud power hogs compared to my particular HTPC). A picoPSU wouldn't cut it in my case, but my system is still extremely low power for what it's capable of. For me, the increase in price of $70.00 from a picoPSU to a silent Seasonic 400w was worth it.
 
#15 ·
Ok, stop. I mis-spoke on the $100 (see below). If you want to call that a win, call it a win.


Now, let's discuss that 15w HTPCs are much more likely to be built into mini-ITX format cases, the vast vast vast vast vast majority of which that will be employed for this task will not support full-size ATX power supplies. They also will not require the "extra connectors" (what a canard, by the way, since you can use "Y" connectors) since they are small form factor units.


Neverminding all this, there is flat out no reason to use a $140 Seasonic power supply in this kind of build. If you are doing a more powerful build with a micro-ATX then maybe the Seasonic is a good choice. But that's not often going to be the case for most 15watt systems. So you can keep pretending this thread is about "somewhat low power systems that have a TDP of >100 watts" but is isn't.


And you can keep calling me out for overstating the price difference by $30 because I used a $70 model of the picoPSU in my link. If you look above, however, to renethx's link, you'll find a $55 version of the power supply (I had linked to a different, $70 model). Check here for the $55 one: http://www.mini-box.com/picoPSU-120-102W-power-kit . So it's really a $140 Seasonic vs. a $55 picoPSU, for a different of $85... Still not $100, but in fact more than twice as expensive.


Given that the new asRock3D uses a 90w external power supply with a picoPSU-type internally, the notion that a 102w is somehow underpowered in one of these systems seems that much more silly.
 
#16 ·
Still a lot of tweaking on mine. Currently @ ~70W idle 170W (normal gaming) full load but its overclocked and has a fairly decent video card. Hits right under 200W with furmark . Pulls about P10k GPU in vantage at 170W. Not completely worried about noise its in another room with HDMI and USB over ethernet. Tried on my GTX295 system and it idles at 200W and goes up to 450W under load.
 
#17 ·
I would say building a box this efficient is only necessary if it's running 24x7, and then it seems to be pretty hard work. If your machine is in S3 for 75% of the day, then the associated power savings are comparable.


My HTPC and WHS are in S3 while not in use (
 
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