Another fanless CPU setup

Shadowknight · Post by **Shadowknight** » Mon Dec 08, 2003 4:49 am

I found this link while browsing Ananad Tech:
http://edwardng.home.mindspring.com/Sigma-001.htm

He uses a Inwin case with a side duct to cool his computer passively. He's running a 2.4 P4, and one of the new Thermalight heatsinks.,

My computer is currently very quiet except for the fan on the CPU. If I can get this to work with my equipment, I shouldn't be able to hear my computer, period (computer is close to inaudible with the side panel off, providing the undervolted CPU fan is disconnected).

Post by **Ralf Hutter** » Mon Dec 08, 2003 5:21 am

I invited him to come over here and post his pics in the Gallery forum but he hasn't done it yet.

He claims 48°C max CPU temp under load.

Here's the thread about this from over at AT.

Trip · Post by **Trip** » Mon Dec 08, 2003 6:08 am

He uses the P4B533-VM for his first system. What board did he use for the 2.4C system? Would almost any board fit in that case?

Ralf, I'll bet his system is quieter than yours

Maybe we should stop referencing people to your system and instead link them to his

silvervarg · Post by **silvervarg** » Mon Dec 08, 2003 7:18 am

He's got a "passively cooled CPU". Is't just that it is located 1 inch from the 120mm PSU fan and 2 inches from the chassi fan (92mm?).

I would say that this is no more passively cooled than a CPU with a Zalman flower heatsink and a fan on a bracket to cool the CPU.

But we should give him credit for building a very silent and well planned system. A good example of a rather simple build with standard components, airflow cooling and negative pressure.

Trip · Post by **Trip** » Mon Dec 08, 2003 7:42 am

Oh yeah, I realised that (I really did this time), I was just joking about it being quieter than Ralf's computer. I dunno, still excited I won the drawing I suppose.

The PSU fan would speed up from all the extra heat. That setup wouldn't beat a system with a PSU channel.

There wouldn't be any noise from a front intake fan though; all the noise would come out the back so it would still be pretty good with his insulation.

I liked the idea b/c you could filter the air coming through the CPU duct and ambient air would be coming through, if you closed all the gaps. A fan on the HS, exhaust fan exchanged w/1 or 2 80mm, and a Seasonic SS with a filtered duct would be ideal, right?

silvervarg · Post by **silvervarg** » Mon Dec 08, 2003 9:13 am

I think some of the real smart thinking with his solution was the controll of the airflow. A normal fan on a CPU heatsink stirs air around in the case producing lots of strange airflow.
With his setup he has rather good controll over the airflow, so he is not reusing any air. He probably had to work a bit with sealing other openings in the chassi. The chassi fan goes to a fanmate, but I guess he still lets that one pull out most of the hot air from CPU.
Ralf can at least teach him a thing or two about how to tidy up among that cable mess.

crypt0r · Post by **crypt0r** » Mon Dec 08, 2003 9:36 am

There's a poster on this board that has a similar case with the 7000 Zalman CPU cooler on it. (Sorry, I don't remember the poster's name). It was posted a few months ago in the gallery forum, I believe. The only issue associated with it is limited hard drive cooling.

GamingGod · Post by **GamingGod** » Mon Dec 08, 2003 10:49 am

Thats the guy that had his 7000 running passively via the side duct on that case that looks like a flower.

Post by **Ralf Hutter** » Mon Dec 08, 2003 12:08 pm

crypt0r wrote:There's a poster on this board that has a similar case with the 7000 Zalman CPU cooler on it. (Sorry, I don't remember the poster's name). It was posted a few months ago in the gallery forum, I believe. The only issue associated with it is limited hard drive cooling.

Yeah, it's this guy. I linked this post to the thread over at AT so they could see someone elses parallel attempt at passively cooling a P4 in an Inwin case.

Seltzer · Post by **Seltzer** » Mon Dec 08, 2003 2:47 pm

Well, its not really fanless cooling... still a good setup, but not truly fanless.

Shadowknight · Post by **Shadowknight** » Mon Dec 08, 2003 3:06 pm

It IS fanless... for the CPU and motherboard. That's why I posted it in the Cooling section.

ez2remember · Post by **ez2remember** » Mon Dec 08, 2003 3:15 pm

silvervarg wrote:I think some of the real smart thinking with his solution was the controll of the airflow. A normal fan on a CPU heatsink stirs air around in the case producing lots of strange airflow.
With his setup he has rather good controll over the airflow, so he is not reusing any air. He probably had to work a bit with sealing other openings in the chassi. The chassi fan goes to a fanmate, but I guess he still lets that one pull out most of the hot air from CPU.
Ralf can at least teach him a thing or two about how to tidy up among that cable mess.

Very good point...

crypt0r · Post by **crypt0r** » Mon Dec 08, 2003 7:38 pm

Yeah, it's this guy. I linked this post to the thread over at AT so they could see someone elses parallel attempt at passively cooling a P4 in an Inwin case.

Yeah...I posted what I posted for the same reason, lol. I didn't mean that this thread is a waste because it's been "done" before. I just wanted to show the people that were interested in this setup another similar setup so that they could gather ideas (since it was apparent they weren't exposed to this case/cooling concept previously).

BTW thanks for finding that thread and linking it. I didn't have time to find it. I was cramming 30 minutes before finals while surfing SPCR hahah...addiction -_-

acj · Post by **acj** » Mon Dec 08, 2003 7:52 pm

Ralf Hutter wrote:
crypt0r wrote:There's a poster on this board that has a similar case with the 7000 Zalman CPU cooler on it. (Sorry, I don't remember the poster's name). It was posted a few months ago in the gallery forum, I believe. The only issue associated with it is limited hard drive cooling.
Yeah, it's this guy. I linked this post to the thread over at AT so they could see someone elses parallel attempt at passively cooling a P4 in an Inwin case.

Hey that's me! People smarter than me always profit off my ideas. The big one someone stole was the braces-less orthodontry system that uses computer designed retainers to move your teeth. I thought of that several years back. Really. Thought it was a dumb idea. haha.

silvervarg · Post by **silvervarg** » Tue Dec 09, 2003 7:17 am

Shadowknight:
It IS fanless... for the CPU and motherboard. That's why I posted it in the Cooling section.

I am not sure I really follow your reasoning, so I wonder what your definition of fanless is. Could you please try to answer a few questions to help me understand. (Free for anyone to answer to see if we can find a common answer.)
Is it important if the fan is attached to the thing it is cooling?
Is it important if the fan has dual usage (e.g. cools 2 or 3 things)?
Is the distance between the fan and what it is cooling important?

A few examples:
Problem1. I have an old machine as server with only the PSU exhausting air (no other case fans). So the PSU fan doubles as case fan in my opinion.
Q1a: Does this machine have no case fan?
Q1b: No forced case airflow?

Problem2: I have a stock Dell computer with a 92mm case fan with a duct to the CPU. The duct does not touch the CPU. In my opinion the case fan doubles as CPU fan.
Q2a: Is this CPU cooled passively?

Problem3: A computer with a Zalman flower cooler and a bracket with a 92mm fan over the CPU (sold as a normal Zalman kit). The NB has a small fan. The 92mm fan's single purpous is to cool the CPU.
Q3a: Is this CPU passively cooled?

Problem4: Same computer, but fan on NB is removed. The 92mm fan is moed slightly so some air spills over the NB and cools that one as well. The fan does now double as CPU and NB cooler in my opinion.
Q4a: Is the CPU passively cooled?
Q4b: Is the NB passively cooled?

Gerco · Post by **Gerco** » Tue Dec 09, 2003 10:12 am

If I may say so...
I think the solution is very simple, if there is a fan in the system, the PC isnt fanless. Because if you have a fan ANY where in the case, there is usually airflow though the entire case which can cool other components as well. Like in this case where the PSU 12 cm fan is right on top of the heatsink for the CPU.

I am also working on an entirely fanless system but I find problems in doing so because components that normally dont need a fan and are cooled enough because of the little airflow through the case like DDR and other small parts are now getting hot and also need to be (water)cooled to keep the temperature within reasonable limits.

So simply said not having a fan on a component like CPU and motherboard can be okay as long as there is some airflow still and you simply make a bigger heatsink or heatpipe and the little airflow that is existent can already cool these components.
A heatpipe does not "cool" a component, it simply transports the heat away from the socket to a large heatsink still where its neats airflow to dissipate the heat. A heatpipe cooled CPU in a case with 0 airflow will get too hot I think. Altho i am not sure about that, I have no experience with heatpipes.

What is correct in this case indeed is the smart airflow control. The more components you can cool with one (big) fan, the more quiet your case will be. It just isnt fanless....

Just my two cents

silvervarg · Post by **silvervarg** » Tue Dec 09, 2003 1:39 pm

Nice to here that someone else is going fanless. I love to read more on your progress as you progress with your system.
As strange as it may sound one of the major components in my fanless design is a fan controller. It will keep track of temps and turn on fans if the passive cooling isn't doing well enough.
If everything work fine I might eventually be able to remove the fan controller and the fans.

Hmm, do you think the DDR will need extra cooling? I was kind of hoping that they would do fine without...

Many heatpipe solutions transport the heat to a heatsink that has one side on the outside of the chassi. On the outside you will surely have some convection cooling moveing the air a little.
The Hush PC and Tranquill PC is good examples of heatpipe cooled CPU's that has prooven to work fine. They have both used the VIA C3 1GHz processor, but resently an ATX chassi was released.

Shadowknight · Post by **Shadowknight** » Tue Dec 09, 2003 2:03 pm

Alright, this is getting irritating...

I never said that the ENTIRE COMPUTER was fanless. I meant that the CPU was fanless. It had no fan. Ergo, the CPU cooling is fanless. That's why I posted that it was a fanless setup in the cooling section, which deals with motherboard and CPU cooling.

There is a system fan. The case is cooled by moving air. The cpu also HAPPENS to benefit. But it still has no fan.

Gerco · Post by **Gerco** » Tue Dec 09, 2003 3:31 pm

not to be rude or so but it doesnt take much to have a fanless setup if you mean only CPU and motherboard, I use watercooling, so I dont have a fan on my CPU either

But yes, I understand your point now.

Silvervarg,
DDR doesnt need extra cooling I think, but in a case with 0 airflow it does get up to 55 Celsius which I find a bit hot. Also that 55 Celsius is being dumped on the inside of my case which doesnt help my case temperature either, that gets up to 50 Celsius currently if I turn all my fans off. Since my case is encased in a bigger case, that doesnt just insulate sound but also heat, so it doesnt take much to increase the temperature there and I think the DDR definitely is a factor in that.
See my case here: http://forums.silentpcreview.com/viewtopic.php?t=8680

Yes a heatpipe with a heatsink outside of the case cools great as seen on http://www.silentpcreview.com/modules.p ... 114&page=1 I just wouldnt use it since as it works great for a CPU, it would be very complex to also use for NB, GPU, HDD's and PSU. With watercooling you can cool all, and easier.

A good fan controller indeed is very important, a while back I could not find one that would let me turn OFF my fans so I added some wiring and switching to my Zalman controller and now in addition to being able to turn it off I also have 12 V and 4V. Which is a bit more and a bit less then the Zalman supplies (5 - 11.5 V)

acj · Post by **acj** » Tue Dec 09, 2003 8:46 pm

The unique thing about this setup, compared to the example with a zalman fan bracket, is the PSU 120mm fan location does not actually have any effect on the cooling. The fan could be in the furthest corner away from the CPU, and it would still be as efffective. But yes, it is needed.

silvervarg · Post by **silvervarg** » Wed Dec 10, 2003 5:31 am

Shadowknight:
I never said that the ENTIRE COMPUTER was fanless. I meant that the CPU was fanless. It had no fan. Ergo, the CPU cooling is fanless. That's why I posted that it was a fanless setup in the cooling section, which deals with motherboard and CPU cooling.

There is a system fan. The case is cooled by moving air. The cpu also HAPPENS to benefit. But it still has no fan.

That is why I wrote:

Is it important if the fan is attached to the thing it is cooling?
Is it important if the fan has dual usage (e.g. cools 2 or 3 things)?
Is the distance between the fan and what it is cooling important?

In my opinion this computer does have a CPU fan, it just doubles as case fan. As I understan you do not count this as a CPU fan, so opinions differ a bit here.
Would it be any different if a 1 inch duct was attached to the fan and the CPU heatsink?
I just try to understand what you think is fanless CPU cooling.
Could you please try to answer the questions in my earlier note?

Acj:
The unique thing about this setup, compared to the example with a zalman fan bracket, is the PSU 120mm fan location does not actually have any effect on the cooling. The fan could be in the furthest corner away from the CPU, and it would still be as efffective. But yes, it is needed.

I don't think I really understood that. Would moveing the PSU further away from the CPU not affect the cooling of the CPU?

Post by **Ralf Hutter** » Wed Dec 10, 2003 6:47 am

Hey Shadowknight - How about just changing the title of your thread to "almost fanless". That way everyone could stop arguing about semantics and get the thread back on topic!

acj · Post by **acj** » Sat Dec 13, 2003 11:57 pm

silvervarg wrote:
Shadowknight:
Acj:
The unique thing about this setup, compared to the example with a zalman fan bracket, is the PSU 120mm fan location does not actually have any effect on the cooling. The fan could be in the furthest corner away from the CPU, and it would still be as efffective. But yes, it is needed.
I don't think I really understood that. Would moveing the PSU further away from the CPU not affect the cooling of the CPU?

That's just what you are missing. It's not the turbulence directly from the PSU fan that cools the CPU (as with a traditional CPU fan). It's the fact that the PSU fan removes air from the case and the only way air can enter the case is through the duct and over the CPU. Not only do all the CFM's of the big 120mm fan pass over the CPU, but all that air is as cold as the outside of the case, rather than the warm air that is usually churned up and recycled inside a case in a traditional setup.

silvervarg · Post by **silvervarg** » Sun Dec 14, 2003 2:10 pm

Acj:
It's not the turbulence directly from the PSU fan that cools the CPU (as with a traditional CPU fan). It's the fact that the PSU fan removes air from the case and the only way air can enter the case is through the duct and over the CPU.

A, now I get your point. That is assuming he has managed to get all other openings in the PC more or less air-tight. Even with some leakage it should work fairly well, so moving the PSU and case-fan away should not matter much.

Edward Ng · Post by **Edward Ng** » Thu Dec 25, 2003 10:59 am

Finally decided to post in this thread for myself.

I'm currently working on sealing all the little openings in the case but the only real wide opening to worry about is that of the front intake, where a fan can be installed (if the darned case came with the mounting cage you need, since it doesn't have standard fan mounting holes!). But on another note...

I just ordered a full set of Acousti Products Acoustifans for this system, to replace the 120mm fan that's in the PSU and the 80mm exhaust fan out back. I also ordered a 92mm piece to install on the HSF, as I am confident I can overclock a little using such a setup, and it will still be quieter than it already is.

The Mod Fathers posted this review indicating that the Acoustifans are even quieter than Papst!!! I'll update as soon as the goodies come in and everything is installed, along with whether or not I used the inline resistors that are included, or any type of rheobus.

All fans, including the newly installed fan on the CPU HS, will be dampened using silicone isolators.

-Ed

PS The monitor buzzing issue I posted about in another part of this forum has been solved. The problem was the system is so quiet (already) that my LCD monitor's buzz became not only apparent but annoying. Someone suggested I raise brightness past 61 (I used to use a setting of 50) and when I set it to 60 or above, the buzz is gone. The monitor then became too bright, but I went and downloaded Entech Taiwan's Power Strip, and placed a -100 setting on brightness with it, and all is good again!

Edward Ng · Post by **Edward Ng** » Mon Jan 26, 2004 4:54 pm

Okay, I received the fans a while ago and finally got around to posting complete details on how I used it; this also includes the most updated info on my machine. Click here for that thread.

-Ed

Another fanless CPU setup

Another fanless CPU setup

done

Re: done

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