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Cooling Processors quietly

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destiriser
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Post by destiriser » Sat Mar 14, 2015 11:05 am

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Sat Mar 14, 2015 4:37 pm

Unless you build with very carefully chosen components, all passive is not very practical. You need a case that allows for some natural convection and you need something like a NoFan CPU cooler. Or you can build small, with a heatsink case like the ones from HDPLEX or Streacom.

Adding a single slow 120mm fan changes everything. A single 120mm exhaust fan and you can build a system with a dedicated graphics card. Big heatsink on the CPU, big heatsink on the GPU and maybe some ducting. Easy.

So why all passive? That's the main question.

If you have a closed case, no airflow and a beefy heatsink on the CPU then you can experiment with levels of load. Heat will build up, how much depends on how fast you run your CPU (let's not cite meaningless TDP-numbers) and how long you let it work hard. If you plan to do some heavy work in the summertime you will probably have to underclock some.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by xan_user » Sun Mar 15, 2015 2:37 am

Vicotnik wrote: So why all passive? That's the main question.
this.

99%+ of people thinking they need a passive system, simply do not. Even amongst SPCR users, the amount of truly passive systems is really low...


I don't remember which SCPR'er said it first...but;
Fanless is pointless.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by edh » Sun Mar 15, 2015 2:40 am

Why the Thermaltake Soprano? That doesn't seem like a good idea for a passive system. If you want to run passive you either need a heatsink case like one of the Streacom's or you want a case with lots of open ventilation. NoFan is an example of a manufacture who does such cases although I'd give most of their cases a miss.
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Post by destiriser » Sun Mar 15, 2015 6:10 am

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Sun Mar 15, 2015 10:17 am

destiriser wrote:From my experience, adding just one outtake 120mm fan on minimum speed doesn't change "everything", it doesn't change much in fact. Adding one to the CPU heatsink does in contrary, but then you have the exact same situation as with fanless rig in closed case, no air movement, so you have to add another fan to that to provide air movement out of the case.
Take a look at this system.
- viewtopic.php?f=14&t=50626

A single fan, close to the big CPU heatsink and with holes in the right places creating some airflow around the graphics card.
destiriser wrote:In the linked Akasa Euler review I read that this case heats very slowly and then stops on certain temperature which is good for tested parts. Let's switch Akasa for my huge closed case with lots of holes here and there. The processor is the same, we just give it some heatsink (that's what the topic is about). It will heat slowly, the case temperature will rise slowly. Then it'll stop at certain temperature, exactly like in the Akasa case.
Well, no. The Akasa has heatsinks on the outside, that's the whole point of that kind of case. With a normal case you will have very little natural convection, causing the whole thing to overheat over time unless the heat output is very small. It's simple physics.

And we cannot tell you if you will stay under 80C with this or that heatsink because what matters is stuff like how easy it is for hot air to exit the case and how hot the ambient air is. And also what the heat output will be, which depends on how hard you press the system.
destiriser wrote:Why put there fans when you can not?
That's my thought exactly. :) Look at my signature. Why do you think I have more than one system? The system I'm typing this on has no moving parts. Nor has my HTPC. Both of these systems are small, close to silent and low power. Checking mail and decoding HD movies are not that taxing.
But for gaming I want at least one fan, because heat management is very complex without fans.

destiriser wrote:I'm not gonna make a render farm from this low power i3 obviously. I'll be browsing web, I'll unpack some big archive, play a game, do some pro audio work, graphics, compile something. All of these won't max out any part of the rig and will rather be near that only for very short times as far as I know. An hour? An hour is a lot of time for air to naturally go out of the case, surely a lot of it will go out.
Underclocking a 35W processor because it overheats with such a heatsink sounds funny to me.
The graphics card will dump more heat into the case than the CPU. So that would be the main problem if you are playing games.
If you put anything but a huge heatsink on a 35W CPU and let it do heavy continuous work in a closed case without ventilation it will eventually overheat. How long it takes I cannot say, because of too many unknowns like I said before.
destiriser wrote:What do you want to cite instead of meaningless TDP numbers? There's no other information on power usage of processors and it's not meaningless since it provides valid information.
Since some 55W CPUs output less power than some 35W CPUs it's not that exact. Much marketing involved. What matters is speed and number of cores. For the current heatsink cases for example, I'd say that a dual core will do fine (talking about modern Intel CPUs here) and a quad will not unless it's underclocked.
destiriser wrote:I want to use Soprano, because I have one, don't think I'd buy such case for a fanless rig :)
But you don't have a fan? :) And researching what fan to buy is such a hassle, not to mention expensive so it's better to spend time in this thread and put some cash into a factory underclocked CPU? ;)
destiriser wrote:On a side note, I think everything will be fanless in near future. Fans are pointless.
Well they are pointless when they are pointless. That is when the heat output is small. This is universal, no need to go all Nostradamus here. :) There is no fan on my Raspberry Pi, but there are fans in the latest SPCR SLI system.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by quest_for_silence » Sun Mar 15, 2015 10:23 am

destiriser wrote:This makes me think that maybe even a 95W intel processor (i7 860) could be passively coolable with a normal heatsink like Macho or one of these Megahalems like towers. What do you think?

It isn't doable, I've already tried some years ago with a passive HR01 Plus on a Core 2 Quad, a passive XFX 7600GT, those feeded by a Fortron Zen, and all inside an Antec Solo: in the long run (well, actually in the short run, a few months) it turned out as a disaster (lots of instabilities, thermal derive during summer, then a beautiful DFI 965P mobo burned).

destiriser wrote:Fans are pointless.

Physics isn't pointless, and fanless cannot go for cheap.

+1 on everything (or so about) Vicotnik just wrote.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by CA_Steve » Sun Mar 15, 2015 10:42 am

Here's an example of a Sandy Bridge i5 (95W) running with a passive tower cooler. Ivy Bridge and later CPUs run hotter due to smaller die and inferior thermal interface. So, yeah, you could get a Haswell i5 to run ok passively with a large tower cooler. With the caveat that you might need to undervolt/underclock it a tad for sustained heavy loads...as the above test was done in an open air environment, and your's isn't. Mugen 2 and it's like should work.
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Post by destiriser » Sun Mar 15, 2015 11:23 am

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Sun Mar 15, 2015 12:04 pm

destiriser wrote:It would be helpful if you added temperatures you get with and without a fan. Also, it's a smaller case, small heatsink, more power hungry processor, more parts and a GPU.
Is it completely inaudible?
Are you talking about the system in the thread I linked to? It's an old system from 2008, I don't have it anymore and I never ran it fanless.
destiriser wrote:I know how Akasa works, it doesn't prove wrong my words that temperature will stop rising. The heat output >is< very small, that's why I choose a low power CPU and nothing else that could overheat in the whole case.
The laws of physics tells us that the heat will stop rising, so no you are not wrong. At some point you will reach an equilibrium. But 35W dumped into a closed case is too much. It's low power, but only so for desktop class stuff. Look at the TDP of the fanless stuff like Baytrail.
Even on a naked test bench 35W is difficult to radiate away. A big heatsink is required.
destiriser wrote:Well, I'm not looking for a gaming super rig, I stressed that a GPU is just an option in the first post, I don't need it. I also said that in case of adding GPU I could add a fan and for a semi-fanless GPU a semi-fanless outtake fan would be a completely viable option.
And I've said that with a single fan it's easy. It's then a normal system. Obviously it's also easy to go fanless if you skip the graphics card, just get a radiator case.
It gets hard when you put hot stuff into a closed space with no ventilation.
destiriser wrote:You can much easier determine what the power output will be when seeing a model and TDP in contrary to just a model even though a 55W model can use less than 35W, you just look at what kind of CPU it is.
I don't think speed and cores matter though, it's rather the tech process it was built in, architecture, voltage and voltage directly correlates with TDP. And well, I'm only looking at dual cores here.
I agree that TDP isn't useless. You can for example see that the Intel Core family is in one TDP range and Intel Atom family is in another.
But between a 35W i3 and a 65W i3 the differences are smaller than the TDP value suggests. And like I said before there are situations where the number is misleading. Slowest dual core celeron vs factory underclocked i7 for example.

If 35W is too much then you will have to underclock/undervolt manually, and then there's little point in going with a factory underclocked CPU in the first place.
destiriser wrote:Yes, fans are pointless when they're pointless. The thing is though that rising voltage isn't efficient, that's why I say that and that there will be more and more fanless and low power tech. Compare the benchmarks of different chips, look at what is happening in the market.
No, fanless NUCs and the like will be a passing fad. I predict that Netburst will make a huge comeback! ;)
destiriser wrote:Anyway, I didn't want this to turn to a discussion about fans and why fanless is bad like every thread I'm finding in google.
It's a discussion about physics.
destiriser wrote:My ambient temperature in summer is like the outside temperature in middle Europe. There's windows open 24/7. The usage is like I said normal, no stressing any part in any way. I suspend everything whenever I can too.
Place the Thermaltake Soprano near that open window and it might work.
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Post by destiriser » Sun Mar 15, 2015 12:16 pm

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by ggumdol » Sun Mar 15, 2015 12:35 pm

As far as I can gather from my experience, the official TDP figures published by Intel are not entirely reliable. To do justice to Intel, they seem to publish some kinds of "upper-bounds" of TDP figures reflecting all possibilities of overclocking and the use of integrated GPU. For example, the official TDP of i5-4430 is 84W, but as far as I can recall, the power consumption of my CPU hasn't ever exceeded 40W (Core Temp 1.0 RC6) and I have also gathered that the TDP figures of i3 CPUs are quite similar, which might corroborate your argument that the number of cores doesn't matter that much. The TDP increases almost (affinely) linearly with the frequency and is also proportional to the square of the voltages.

It might be possible to go fanless with some latest i3 CPUs (note that Atom and i3 belong to completely different leagues in terms of TDP, as Vicotnik mentioned) with formidably gigantic coolers (I don't have much expertise because I haven't bothered about them). However, if you intend to use the fanless PC in the long run, I reckon that you will eventually have concerns (even if you don't have them right now) about the resilience of your fanless PC. To resolve those concerns, I would attach a PWM fan of 120 or 140mm which can rotate as low as 300 RPM, e.g., Noctua fans (Warning: not so many fans rotate at this low speed. That's why I prefer Notua fans). You can't hear them as long as you are a human.

I'm one of serious silience-seekers as many people in this forum are. However, in general, I don't think it's a pragmatic idea to go fanless with an i3/i5 CPU until 2017 by which time Intel will be churning out 10nm CPUs codenamed "cannonlake".
destiriser wrote: You can much easier determine what the power output will be when seeing a model and TDP in contrary to just a model even though a 55W model can use less than 35W, you just look at what kind of CPU it is.
I don't think speed and cores matter though, it's rather the tech process it was built in, architecture, voltage and voltage directly correlates with TDP. And well, I'm only looking at dual cores here.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Sun Mar 15, 2015 12:52 pm

destiriser wrote:What makes you think 35W is too much? Were there tests, did someone try it? I'm sure I would try it if I had a chance.

CPUs with 30W and lower TDP are used in laptops with such a tiny fans and tiny radiators and they work properly.

I wouldn't have a problem with buying a big heatsink like Mugen for that.

I don't see what's wrong with factory underclocked CPU, it has the same price.

The case can be placed under the window.
There's a big difference between a little airflow and no airflow. This is again physics.
http://en.wikipedia.org/wiki/Heat_transfer

With a big heatsink like the Mugen, the case open and with some air movement thanks to the open window it could work unless you stress the CPU much.

Regarding factory underclocked CPUs they are really only needed if you want to stay within a tight power envelope and underclocking manually isn't an option. Like the i3 2100T in my server; I wanted to make sure I could run the system with a 60W brick and I'm unable to underclock manually with that motherboard.
If you are into underclocking to make the fanless system work even on the hotter days with no wind you probably want a motherboard with overclocking (underclocking) capabilities and then all a factory underclocked CPU does is to give you less headroom should you later want to crank up the speed.

Couldn't you do some testing with your current system btw? Some practical testing with stopping the CPU fan etc should probably give you some hands on experience. How much is 35W anyway?

I've run a Tualatin Celeron fanless back in the day. It's TDP was 29W at stock speed and I both underclocked and undervolted it to an estimated 10W. I was then able to run it semi passive with a pretty small heatsink. But there were case fans because the HDDs in that system needed cooling.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by quest_for_silence » Sun Mar 15, 2015 12:57 pm

destiriser wrote:I'm not sure why you'd run it like that when it was overheating. Anyway, I believe you didn't use a good parts for fanless system to say it isn't doable, cpu is old, gpu unneeded and power hungry, case seems to be a normal closed one, I don't know about the PSU and heatsink, but there's definitely a lot of room for experimenting, don't say it's not doable.

You grossly misunderstood: I'm talking about a system of about 7 years ago, when the CPU was new, and its thermals were comparable to the quoted i7-860 (the reason why I recalled that rig), so your beliefs are totally wrong.

I never run that system in an overheating condition, as a matter of fact: I said you that the thermal balance achieved in the fall were completely subverted by the higher ambient temp of spring and summer.
So, while the CPU was running inside the Intel recommended thermal envelope (but 10-15°C more than before), the whole system strived to find a new balance due the increased case temperature. I cannot say wheter this fact actually killed the mobo, but it's a very important factor for any degradation in electronics.

I think that's due to your somehow deep lack of knowledge: your Soprano isn't that good thermal wise, stripped to the bones it's basically a ten-years old design with a not particularly good airflow (and so it is comparable to the Antec enclosure in many respect when used to run a completely passive system). And if you think a Megahalems can run passive under any scenario, well, you are the one who pick the wrong parts for that task.

But in the end, from your words I perceive how it's perfectly useless that I explain you more about these things: you will have to lift the heavy veil of your ignorance on your own, as everybody did before, I wish you good luck.

destiriser wrote:I just mentioned Akasa Euler, is it really not cheap in comparison? Add to that the fact that it's a new tech, it will get cheaper and the fact that all the computer parts are lesser and lesser power hungry.

As you may easily see, I've talked of a Core i7 860 passively cooled in a Soprano with a Megahalems, quoting these parts from your OP. The Akasa Euler was not an option in my considerations (and in your quoted ones).
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by quest_for_silence » Sun Mar 15, 2015 1:01 pm

Vicotnik wrote:Place the Thermaltake Soprano near that open window and it might work.
+1
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by edh » Sun Mar 15, 2015 2:16 pm

Vicotnik wrote:Place the Thermaltake Soprano near that open window and it might work.
Better still, give it a nice firm push out of the window. :lol: It might still have scrap value after that.

Then buy a case that is better intended for the purpose.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by xan_user » Sun Mar 15, 2015 7:01 pm

Fans are pointless.
personally i feel that fanless is actually pointle$$.
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by bobb » Sat Mar 21, 2015 2:56 pm

Whoa, this thread is giving me a headache.

Some of u are concerned about the enclosure's temperature, while this is one item, shouldn't we be more concerned about the DIE temperature at the CPU/GPU? On that little square, lots of heats can be generated fairly rapidly and it needs to be dumped out, reason why big heatsinks are there. Once I booted a CPU without heatsink just to test something quick and the temp went up within seconds, I quickly shut it down under 1 minute not wanted to take any risk. The box's temp rise slowly but the DIE temp - BAM!

Here seems to be the talk of, "Oh am not going to push this box, if hardly, I can get away with..." Okay, but I believe most of us design our stuff to deal with worst case scenario, because I for one having an v12 will not want to ease the throttle when my water temp goes into the red.

If you don't do gaming (disregard board games, simple games) there is no need for external GPU these days. The iGPU of last couple of years have enough juice to run 1080p video. If you have external GPU, that DIE too needs to be cooled and heat dumped out.

I do agree that Intel and others are on their way, with help from Apple, to make everything more efficient after each generation, so in the future, no fan maybe necessary. The recent announced Macbook retina is fanless.

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Pappnaas » Sat Mar 21, 2015 5:59 pm

xan_user wrote:Here seems to be the talk of, "Oh am not going to push this box, if hardly, I can get away with..." Okay, but I believe most of us design our stuff to deal with worst case scenario, because I for one having an v12 will not want to ease the throttle when my water temp goes into the red.
If you are rich enough to by a new one every time the old engine blows of due to misregarding laws of physic, then move on. If not, either trust our experience or learn yourself.

Besides, the point was fanless makes no sense, because a silent slow running fan still makes no noise. And if i can't hear it, but my systems runs reliably, why make a fuss?

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Sat Mar 21, 2015 11:13 pm

bobb wrote:Whoa, this thread is giving me a headache.

Some of u are concerned about the enclosure's temperature, while this is one item, shouldn't we be more concerned about the DIE temperature at the CPU/GPU? On that little square, lots of heats can be generated fairly rapidly and it needs to be dumped out, reason why big heatsinks are there.
It helps to think of it as heat and forget about temperature. The CPU core is the source of the heat. We don't want the core to overheat, so the heat needs to be transferred in some way, all the way to the ambient air usually.

Notice that when we talk about CPU cooler performance we talk about temperature rise over ambient. Thus ambient temp is a part of the equation and should not be disregarded.
bobb wrote:Once I booted a CPU without heatsink just to test something quick and the temp went up within seconds, I quickly shut it down under 1 minute not wanted to take any risk. The box's temp rise slowly but the DIE temp - BAM!
Yeah, overheat protection is a nice thing to have. Had you tried that a few years back you would within seconds see a little bit of smoke coming from the die and then the CPU would be fried, and if you're unlucky take the motherboard with it. Today the thing shuts down or even throttles down to a point that it actually can keep running.
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Post by destiriser » Wed May 06, 2015 3:31 am

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Wed May 06, 2015 10:58 am

Yeah, you need a board with overclocking features to be able to undervolt. Underclocking is usually still doable by simply lowering the multiplier. If you plan to let the CPU do heavy work for long periods of time I would consider a factory underclocked CPU if you are unable to undervolt manually. I still wouldn't recommend heavy work for a totally passive system, but it's certainly doable.

I would not recommend a quad core, they get too hot in a small heatsink case in my experience. In normal use there would be little difference, they all idle the same etc. But at full load twice the number of cores makes a difference. Jobs that can be parallelized will finish twice as fast, but the peak power load for the CPU will also match the performance. More than 10W difference for sure.

I'm curious, why the Akasa Euler? It's a bit old and personally I'm not thrilled about the aesthetics. I like the HD-PLEX cases better. :) But the Akasa Euler should be cheaper.

The brick you have should be fine.
Main: ASRock B85M-ITX | i3-4330 | 16GB DDR3 | Intel 730 240GB | HDPLEX H1-S | picoPSU | No moving parts | Idle 13.9W
HTPC: ASRock J4105-ITX | 4GB DDR4 | Intel 535 120GB | picoPSU | No moving parts
Gaming: Intel DH77EB | i5-3570K | GTX 1060 6GB | 16GB DDR3 | TJ08-E | RM750X
Server: ASRock N3150-ITX | ~30TB | G-360 | Idle ~25W

destiriser
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Post by destiriser » Wed May 06, 2015 1:32 pm

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Last edited by destiriser on Tue Mar 01, 2016 3:50 am, edited 2 times in total.

Vicotnik
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Wed May 06, 2015 2:09 pm

destiriser wrote:I'll go for that normal i3 with better gpu then. It's the most cost effective processor here. i5 is not only more expensive but also uses more power, lots of drawbacks and if underclocked it won't even be faster than i3 core vs core, but slower. I'll rather switch to newer processors more often and hope that the TDP lowering will progress. I'm a bit afraid of these new 12 core 140W intel processors though :)
Sounds very nice. Normal i3 with best GPU was my choice as well, for my last two main systems. Intel DH77DF and i3-3225 before and now ASRock B85M-ITX and i3-4330.
destiriser wrote:I quite like how it looks, especially that S version: http://www.akasa.com.tw/update.php?tpl= ... -ITX10-A1B
Yes, it's not bad. I'm a bit picky about big logos though. I pay extra for that clean slab of aluminium. :)
destiriser wrote:Also, about my setup. I'll also set up a home server (hidden and unhearable) on old Atom chip (D525, twice less idle power usage than Haswell), there will be HDDs will lots of space, it will do as router too (because my current D-Link is unbelievably bad), XBMC, cloud and possibly some other stuff. This passive PC will be an HTPC too with a big monitor that I bought for it. It'll be connected with a gigabit ethernet cable, so no wifi slowness.
Great. I think it's nice to break functionality into different neat systems that can be upgraded and maintained independently. The home server is the core of that. :)
Main: ASRock B85M-ITX | i3-4330 | 16GB DDR3 | Intel 730 240GB | HDPLEX H1-S | picoPSU | No moving parts | Idle 13.9W
HTPC: ASRock J4105-ITX | 4GB DDR4 | Intel 535 120GB | picoPSU | No moving parts
Gaming: Intel DH77EB | i5-3570K | GTX 1060 6GB | 16GB DDR3 | TJ08-E | RM750X
Server: ASRock N3150-ITX | ~30TB | G-360 | Idle ~25W

destiriser
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Post by destiriser » Wed May 06, 2015 2:31 pm

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Last edited by destiriser on Tue Mar 01, 2016 3:50 am, edited 1 time in total.

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Wed May 06, 2015 2:53 pm

And without USB ports on the front as well. Damn.. Very sleek. Had I know I would probably have built my HTPC in one instead of a second HD-PLEX case.
Main: ASRock B85M-ITX | i3-4330 | 16GB DDR3 | Intel 730 240GB | HDPLEX H1-S | picoPSU | No moving parts | Idle 13.9W
HTPC: ASRock J4105-ITX | 4GB DDR4 | Intel 535 120GB | picoPSU | No moving parts
Gaming: Intel DH77EB | i5-3570K | GTX 1060 6GB | 16GB DDR3 | TJ08-E | RM750X
Server: ASRock N3150-ITX | ~30TB | G-360 | Idle ~25W

UHF
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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by UHF » Fri May 22, 2015 10:42 am

I think the powers that be here should write a nice long article on fanless and its issues. It might reduce the torrent of fanless PC requests from newbs.

Incidentally I did indeed build a fanless PC years ago with a big heatsink in a sealed box. It was an MP3 player. It consumed 65W, and it got mighty hot in that box. So, I cut some vents in the lower sides of the box, and in the top. The case had a nice heavy air flow after that, and it dropped the temperatures to a toasty 40C from 60C or so. (Back then PC power consumption didn't vary much...)

I think the issues that frequently crop around all this is air circulation or the lack there of, power control for your CPU (underclocking, undervolting), GPUs and what to do there. Power supplies, and drives are also a concern. Many folks are missing some of the potential follow on issues, namely what if your board develops a 4k whine 3 weeks after it starts working. I think that some concerns around electronic degradation can be ameliorated by looking into more reliable parts. (Gaming PCs are built to take more abuse, so I think they'll be more reliable in a more passive situation.)

All that aside, I'm still planning to build my own 'fanless' PC, but I'm expecting to put a single fan on it anyways, just in case. :-)

destiriser
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Post by destiriser » Tue May 26, 2015 3:03 pm

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Last edited by destiriser on Tue Mar 01, 2016 3:50 am, edited 1 time in total.

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by xan_user » Tue May 26, 2015 5:33 pm

congrats!
perfect example of how to successfully go fanless. get the right, low power parts, and put them in the right case (that's also the heatsink).
Help SPCR keep the lights on, use these links when you buy: NCIX, Amazon and Newegg

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Re: What fanless cooler (heatsink) for 35-65W intel CPUs?

Post by Vicotnik » Thu May 28, 2015 3:34 am

Nice system destiriser. :D

I've never maxed out on temperature on my fanless systems, as far as I know. It's not the CPU I worry about, but all the other stuff in the box that gets cooked if the system is pushed hard for long periods. I write a little bit about the systems in the gallery thread linked to in my sig.
Main: ASRock B85M-ITX | i3-4330 | 16GB DDR3 | Intel 730 240GB | HDPLEX H1-S | picoPSU | No moving parts | Idle 13.9W
HTPC: ASRock J4105-ITX | 4GB DDR4 | Intel 535 120GB | picoPSU | No moving parts
Gaming: Intel DH77EB | i5-3570K | GTX 1060 6GB | 16GB DDR3 | TJ08-E | RM750X
Server: ASRock N3150-ITX | ~30TB | G-360 | Idle ~25W

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