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Thanasis posted on Sun, 15 Mar 2015 21:44:54 +0200 as excerpted: |
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> On 03/15/2015 09:08 PM, Leonid Eremin wrote: |
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>> |
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>> But here's 2 major cons [of high-power power-supplies]: |
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>> 1. high power PSUs are less effective at low power usage. |
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> |
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> Maybe if consumption is less than 10% of the PSU's rating, ie less than |
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> 30W for a 300W PSU. |
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|
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My ideal would be a reasonably low-power, passively cooled (no fans) |
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power supply. Low power because high power passive-cooling gets |
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massively heavy and expensive. Passively cooled as it's for a router to |
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which among other things my VoIP phone adapter connects, which means it's |
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going to be on all the time, and thus needs to be silent or nearly so, at |
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least at low usage. |
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|
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On my main machine both the CPU and PSU fans are heat controlled, the PSU |
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fan automatically on its own, the CPU fan configured that way in the |
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BIOS. However, while the main CPU fan can actually stop if the temp is |
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low enough (in the winter when I first turn on the machine, I get the |
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warning buzz for a minute or so as the fan isn't on yet, until it warms |
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up, and I have a minimum speed set below which I get a buzz as under |
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normal operations it won't be going that slow), the PSU fans don't turn |
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down low enough and can bother me if I leave the machine on, say playing |
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rain sounds, when I'm trying to sleep. |
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|
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Which is why I jumped at the idea of having the router play at least |
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music-only and still-frame youtube, etc, in an earlier reply, once I saw |
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it discussed on that media-player-machine forum. |
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|
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At some point, I'll probably buy a new PSU for the main machine too, as |
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the current one is massively overpowered for the job, but it's what I |
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had. (This PSU originally powered my old dual-socket original-3-digit- |
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opteron machine, which I was at one point running with four spinning-rust |
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disks in raid, etc, so it's 850 watt IIRC, while my kil-a-watt says the |
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entire system including LED-based TV/monitors rarely tops 400 watt, |
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meaning the computer itself should do fine with a 250-300 watt power |
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supply, tho I've been going to kil-a-watt check it one of these days to |
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see what it actually takes, and haven't yet.) But meanwhile, if I'm just |
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playing stuff like 12-hours-of-rain while I sleep, with the new amd64 |
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router, I might as well simply use it and turn off the main machine. |
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|
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But since the router /is/ going to be on all the time, connecting the |
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phone adapter if nothing else, I'll definitely want quiet, if not |
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/entirely/ passive, CPU /and/ PSU heat sink/fans. |
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|
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For the side of the main machine, I did buy at frys some time ago a big |
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8"/200mm fan, 750 RPM, IIRC 110 CFPM, that's close to silent. Ideally I |
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could put something like that in the side of the router to ensure |
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reasonable circulation, and go entirely passive on the CPU cooler at |
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least. I know at 250 watt and so they have passively-cooled PSUs as |
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well, but I've not looked into it /too/ deeply yet. I want the thing up |
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and running first, and plan on tweaking things like the PSU, if |
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necessary, afterward. |
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|
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But if I can find something reasonably cheap and near enough to silent, I |
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might as well get it from the beginning. Which (besides simply running |
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out of time) is the reason I more or less just picked a reasonable case/ |
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psu number and ran with it for that baseline cost estimate. |
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|
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>> 2. more expensive, after all. |
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> |
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> Not necessarily. Is $45 expensive for a 300W PSU like |
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> http://www.newegg.com/Product/Product.aspx?Item=N82E16817151113 |
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|
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Well, considering the one case with 250W PSU newegg was offering on |
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bundle was $50, $45 for the PSU alone, at a decidedly run-of-the-mill |
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300W, is indeed "expensive". |
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|
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But two things to note about that particular PSU. |
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|
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1) It's not standard ATX. It's TFX12V, which since I'm looking at SFF |
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(small form factor) cases, may be useful, depending on the case I get, |
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but it's definitely NOT the standard power supply most people will be |
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most familiar with. (FWIW, I just looked it up and wikipedia's power |
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supply unit (computer) page has a short mention/description of TFX12V |
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under "Other form factors", while to the extent it's different, most of |
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the page covers ATX. TFX12V is described as common for small and low- |
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profile systems like mATX and FlexATX, and some of the smaller mITX |
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cases, mITX being the board and cases I'm looking at, may standardize on |
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it too.) |
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|
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https://en.wikipedia.org/wiki/Power_supply_unit_%28computer% |
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29#Other_form_factors |
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|
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So it's /not/ a standard ATX power supply, likely accounting for at least |
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part of the reason it's $45 for only a relatively low-power 300 watt, |
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since TFX12V won't get the same manufacturing volume and thus discounts. |
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|
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Non-ATX power-supply-cases is part of the additional research I'm doing, |
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so when I saw the PSU photo, I immediately picked up on the non-ATX size |
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and checked what it was, then looked that up, as I've not memorized the |
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various abbreviations yet. |
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|
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2) This PSU /does/ say "super low fan noise" in the specs, and the |
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reviews seem to agree, tho the noise level in dB isn't actually |
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quantified for comparison purposes. |
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|
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I'd be a bit skeptical of the feature claim on its own without an actual |
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comparable dB quantification, but the reviews do alleviate my skepticism |
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somewhat. That may be an additional reason for the price. |
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|
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And of course it's gold-plus certified efficiency, with an 87% efficiency |
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number claim. Again, justifies a bit higher cost. |
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|
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So all in all, while I've yet to do PSU comparisons and may not need to |
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if I buy a case/psu combo, $45 doesn't sound unreasonable, given the |
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three points above. I'll have to keep this one in mind as I do my case/ |
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psu shopping, as it may just fit the bill perfectly if I buy a case |
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without bundled supply, that fits TFX12v, not ATX. |
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|
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman |