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Discussion Starter · #1 ·
I've been doing some research on low wattage HTPCs to hook up to my new plasma. It seems that some of the best ones out there are the atom/ion jobbers. Is it possible to build a low-power PC out of cheaper, larger hardware? My TV is mounted on the wall and I can put the PC in the room behind it, so I don't really care how small or pretty (or quiet for that matter, but quiet would be good) the computer is. I just need it to do Windows 7 smoothly with Mediabrowser for my SD DVD rips. I have another computer with a 780G chipset and it's rather slow going through Mediacenter/Mediabrowser, especially if something is playing. I'm not even planning on going the BR/BR-rip route at this point.
 

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Discussion Starter · #2 ·
Looks like there are a few single core processors out there that have a TDP of 35W or 45W and a whole slew of processors that have a TDP of 65W.


Would a more efficient power supply actually be the answer here? From some of the poking around I did, it appears that the new 890G chipset isn't really any better than the 780G/785G chipset, but it will do Directx 10.1. I will keep digging.


Perhaps I should just get a Dell Zino or a Mac Mini, but it seems like I could get a better computer in a larger package.
 

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Quote:
Originally Posted by perpetual98 /forum/post/18242663


Would a more efficient power supply actually be the answer here?

If you want the PC to consume less power, choose a properly-sized PSU as well as one rated for efficienty (80Plus). By "properly sized" I mean a PSU that has a capacity appropriate for the load. It is common to see build stories or suggestions for HTPCs with 500 watt or larger power supplies. A switch-mode power supply should have a 20% load to maintain its efficiency. So a 500-watt supply needs a minimum load of 100 watts (20% of 500 watts). But a typical HTPC with a "65 watt" CPU, IGP and a few drives will consume less than 40 watts at idle. So this big PSU still needs about 40 watts for basic operation, and ends up running at only 50% efficiency (40w out, 40w waste). You have an 80Plus PSU but it is being operated below its optimum range.


If you had a 200-watt 80Plus power supply, that small HTPC load would use only 50 watts total (40w /80%) at idle versus the 80 watts (40w / 50%) of the big PSU. Instant 30 watt savings by using the properly-sized PSU for the same PC. (I actually did a similar PSU swap.)
 

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TDP is at max load I believe. So a dual core processor at 65w TDP might actually use less than a single core 45W. Honestly I wouldn't worry about saving a couple watts as it'll cost you a lot in performance. Makesure you get a good powersupply that is super efficient though as it'll save you the most. Also consider sleeping/turning off the machine when not in use, that'll save you the most.
 

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S3 sleep seems to use about 5watts. which is what I use. Also I can hit the sleep button on my wireless keyboard to turn if off and on.
 

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Quite frankly, you're the only one I know of who's having difficulties because of wanting to building a regular-sized desktop. Most of the posts I've seen are of people having trouble trying to build ultra-tiny computers.


That said, power supply can help a lot with lowering power consumption. For a low-power HTPC build, something like the Seasonic S12II 330 Bronze should work nicely. You could actually go lower, but it's hard to find an efficient, good quality PSU under 300W. The PicoPSU is an option but they tend to be more expensive than regular ATX power supplies, not to mention you'd have to do something about the huge gaping hole in the case where the PSU is supposed to be.


No need to go single-core when 65W TDP processors could have similar power consumption at idle and while their load power consumption might be higher, they're also able to finish tasks faster. Lower end Athlon II X2 Regors and Celeron E3x00 and Pentium E5x00 Wolfdales make for very nice low power, inexpensive HTPC processors. The new Core i3 Clarkdales are pretty nice but I think there's a bunch of driver issues that need to be worked out first.


By the way, it's possible that there's nothing wrong with your 780G PC (just curious, what processor do you have?). MediaBrowser devs are aware that it's slow and are trying to speed the program up.
 

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A more efficient power supply is going to make the biggest difference, ideally, a solid state passive power supply is going to be the most effective. PicoPSUs and like often have efficiencies over 90%, though you're capped around 200W for them.


Also, TDP is the total power that the chip was designed to need in long term, full load use, with frankly inadequate cooling. The warmer a cpu runs, the less efficient it will be, primarily in the log term. Never expect a CPU to use the full TDP at stock speeds out of the box. They(for the most part) don't.


Finally, there is no way to beat the performance/watt of an ION system, just not going to happen, it's exactly what they're designed for. A few years ago the big thing was to use mobile CPUs in desktop boards to run as low power as possible, but you can get a modern quad core with the same idle and low load power use as the single cores of that time.


I did have to LOL at your post though, you bought a plasma, and now want an energy efficient HTPC to run with it, why not get an LED/LCD and save more power than your htpc is likely to consume in the set, then build the HTPC for 0 net energy use compared to the plasma.
 

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Discussion Starter · #8 ·
Good points. I wasn't really having a problem with a build, just wanted to get some discussion going.


I was just trying to save power where I could. I know that plasma uses more power than LCD, but when you get a deal on a new plasma, a deal is a deal



I haven't tried using S3 on my main HTPC because I've just heard of too many problems, but it's something that I should probably look into. I was just leary that I would miss recordings. The HTPC I'm thinking about building for the new theater in the basement would probably just be getting recorded TV from that and wouldn't need to be "awake" 24/7.


*EDIT* Just looked at the spec sheets of the 2 TVs I'm deciding between. A 46" LCD (Mitsu) and a 50" Plasma (LG) and the power consumption on the LCD was 315W and the plasma was 295W. So who knows.
 

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I've never had a problem on any of my win7 machines with S3. win7 made it super fast too my laptop completely resumes from S3 before I even have the lid open.
 

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Discussion Starter · #10 ·

Quote:
Originally Posted by justinm0424 /forum/post/18243400


I've never had a problem on any of my win7 machines with S3. win7 made it super fast too my laptop completely resumes from S3 before I even have the lid open.

Maybe it's about time I start looking at S3 then.
Heck, I'd just turn the darn PC off if it was up to me, but the wife tapes some stuff during the day when we're at work.
 

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Quote:
Originally Posted by ArtosDracon /forum/post/18243085


Finally, there is no way to beat the performance/watt of an ION system, just not going to happen, it's exactly what they're designed for.

Absolute power consumption, yes the Atom/ION wins. Performance/Watt it would probably lose to faster, low-power chips such as the Core i3 or 785G+240e.
 

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Quote:
Originally Posted by ilovejedd /forum/post/18243696


Absolute power consumption, yes the Atom/ION wins. Performance/Watt it would probably lose to faster, low-power chips such as the Core i3 or 785G+240e.

I guess I should have specified the comment towards HTPC playback as that is what I was inferring, just quite poorly. Overall performance or performance during heavy load will likely go to the lower power desktop board.


In a quick couple searches I couldn't find comparisons to anything very modern, and certainly none of the low power boards, but if you consider that zotacs 330 Ion boards idled around 25W, and most modern desktops idle around 60W according to every review I've seen, even a low power version is not going to idle at half of the desktop, let alone atom low. Even looking at the IONs load power numbers being around 35W, that's gonna be really difficult to see a desktop cpu in a desktop board beating at idle.
 

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Quote:
Originally Posted by ArtosDracon /forum/post/18244007


most modern desktops idle around 60W according to every review I've seen,

I have measured several basic desktops that I have using a Kill-a-Watt meter.

One PC idles at 55 watts and another at 60 watts. That's watts drawn from the wall outlet. These PCs do not have 100% efficient PSUs, so the actual power load on the PSU is about 40 watts.


I don't have an Ion, but a dual-core Atom D945GCLF2 with a generic 200w PSU consumes only 10 watts less at idle as a dual-core AM2/GeForce 6150 setup w/80Plus PSU.
 

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Quote:
Originally Posted by ArtosDracon /forum/post/18244007


In a quick couple searches I couldn't find comparisons to anything very modern, and certainly none of the low power boards, but if you consider that zotacs 330 Ion boards idled around 25W, and most modern desktops idle around 60W according to every review I've seen, even a low power version is not going to idle at half of the desktop, let alone atom low. Even looking at the IONs load power numbers being around 35W, that's gonna be really difficult to see a desktop cpu in a desktop board beating at idle.

Most modern reviews tend to have discrete graphics and on a very low power machine, the additional power consumption is quite significant. They also tend to use 1000W power supply which drops efficiency to well below 80%. Check out reviews from SPCR and user comments on the SPCR forums and you'll see it's quite possible to build desktops with very low power consumption. Tom's was able to get Core i3+H55 system down to 25W idle simply by using an 80Plus Sparkle 220W PSU and replacing the 3.5" drive with a 2.5" (forgot if it was SSD or notebook drive).


Here's a build I did this morning:

Specifications
  • Case: In-Win BQ656
  • PSU: IP-AD80A7-2 (80W unknown efficiency, proprietary form factor)
  • MB: Zotac GF9300-G-E
  • CPU: Intel Pentium Dual-Core E6300 (Wolfdale)
  • GPU: NVIDIA GeForce 9300 (iGPU)
  • RAM: Kingston 2x2GB DDR2 800 CL6
  • HDD: Seagate Momentus 5400.5 320GB
  • ODD: Pioneer DVR-TS08

Power Consumption
  • Off: 2W
  • Boot: 55W
  • Idle: 35W
  • Load: 78W


Load testing was done with IntelBurnTest (1/2 memory) which is supposed to stress the CPU better than Prime95. Alas, it fails immediately when I use the max memory option but I suspect it may have to do with the fact that I'm using Windows 7 32-bit. Will install Windows 7 64-bit tomorrow and test with that.


I bought the Pentium E6300 a while ago to upgrade one of my other computers. Never did get around doing it so I ended up using it for an entirely new build. Had I not had this processor, I would've gone with a Celeron E3x00 instead which should have even lower power consumption.


From what I recall, when I built my Zotac IONITX-A-U, idle power consumption I got was 24W.

Specifications
  • Case: Mini-Box M350
  • PSU: 90W (included w/board)
  • MB: Zotac IONITX-A-U
  • CPU: Intel Atom 330
  • GPU: NVIDIA ION (iGPU)
  • RAM: Kingston 2x2GB DDR2 800 CL6
  • HDD: Western Digital Scorpio Blue 500GB
  • ODD: none
 

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Discussion Starter · #15 ·
Good info! I should dig out my Kill-a-watt and see what my various PCs are drawing.


Are the Zotac type iGPUs rated about the same power as a 780G? I haven't done much research in the REALLY small boards, but they do look sharp.
 
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