Fanless water cooling, is this enough?

Hi,

I tried to get some good answers on Swedens biggest computer-forum but didn't really get any. What I want is to have a fanless water cooling system. Just have fans mounted in stand-by if I need them.

What I got to cool is:
1x i7 6700K
2x 980 Ti strix
1x motherboard

And I do use a R5 chassi. What I got in the chassi right now (thanks to some modding):
2x 280 radiator
1x 220 radiator
1x 5.25" reserovar with D5 pump
1x D5 pump with 140 res
1x 140 rad (on the back outside the chassi).

What I have ordered and aim to do:
Mount 2x480 radiators underneath my PC-desk and connect it to my cooling loop using on-off and push-fittings. So that I can easily remove them if I need to move my PC.

My plan is to mount fans on the radiators inside the chassi and have them ready, so if I need them I turn them on. But otherwise I want them off. I will also use noise-reduction carpet and use them on the pumps to reduce the noise.

What I wonder is:
1. Will 2 D5 pumps be enough for this? I did order another one so I got 3 if I need. But don't want to open the last one because then I can't refound it!

2. Wil I be able to use this loop without fans?

3. If I cover my pumps in silencing foam carpet (what is the actual word for this?) will they overheat?



Nothing in the loop is finished yet. Some parts are in place but not filled with water. So if anything sucks in this system them please tell.


Best regards

I suspect that you have enough cooling power to cover your bases but the biggest concern I have is your plan to insulate the pumps with foam carpet. By insulating pumps you will be causing your temps to rise even more because the water will be passing through hotter pumps, probably much hotter than they would be if it were not insulated. So you would be working against your goal of cooling. Also realize that the fans in your case may make enough noise to mask the pump noise without insulation. In short, I think insulating the pumps is a bad idea.

For what it's worth, I can't even hear my fans right now, and I'm 1.5 feet away.

I run my system pretty much fanless, as a rule a 4790K, overclocked, cpu only.
I use 2 9x120 rads, 1 3x120 rad and lots of res.
I can go a couple of hours gaming passive but once heat starts to build in the system I have to start a fan or two.

caddi daddi said:

I run my system pretty much fanless, as a rule a 4790K, overclocked, cpu only.
I use 2 9x120 rads, 1 3x120 rad and lots of res.
I can go a couple of hours gaming passive but once heat starts to build in the system I have to start a fan or two.

Click to expand...

Man, you can cool a car engine with that much radiator space.

just junk I had laying around.
the only thing in the cases are blocks and tubes with quick disconnects.

I will never understand the fad of going "fanless" in PC builds. In the context of water cooling, rads use high density fins that are designed specifically for fans, so trying to use such a rad without fans makes very little sense at all. You would really need a different kind of radiator altogether, something more efficient for fanless cooling, and even then it would likely eventually need active cooling of some sort because the heat would build up over time.

So, in short, to answer your question: no, you can't use your proposed loop without fans because WC isn't designed to operate passively.

lenny, you are right, but with enough water acting as the heatsink you can go quite sometime before you need to bring the fans in.
as far as understanding, nobody had to, some folks just like to tinker around.
I don't understand you people across the pond driving dinky little cars, I don't have to understand it, I just have to let you do it.

I ran a silly water cooling experiment I ran recently, which I still need to write up. In that, I had about 10L of water and no radiator or forced air movement. Processor was 65W TDP (it was overclocked so would be a bit more than that) and it took about 8 hours running prime95 before CPU reached 75C that I had with the air cooler before that. I think start water temps were low 20's C, going up to mid 30's C before I stopped the experiment. With a large volume to hold the heat, and a large enough surface area and moderate loads, I can imaging it being possible to run like that. Before anyone questions the differential between water and CPU temps, this was not any conventional setup, but still illustrates the heat transfer and storage in the water.

I also think any low speed fan will help a lot over no fan, and it should be quiet enough not to be noticed.

The more capacity(water) you have, the longer it will take to heat up... but it will eventually heat up with no fans...

When I built my system, my intention was to be able to run it passive, if I wished it. I use an MO RA3 420, 2 x D5s, had 2 x 970s and a 5820k. I also use 2 very large reservoirs. My ultimate goal was to be able to keep the coolant within 12c of ambient. If it went over, I kicked the fans on. During gaming sessions, an hour or maybe a little longer, I'd find myself kicking the fans on. Just browsing the net, streaming a movie and such, it'd go 3 or 4 hours before I even looked at the temp sensors.

Really though, with this rad and the 4 x 230mm fans that run on it.....I can barely hear the fans at all, and that's with the side panel open. /shrug

Any fan will be MUCH better than no fans. So I'd recommend using fans wherever you can, just use ones your can't hear or under volt them. As said by others, PC radiators are designed specifically to be used with fans.

I once ran one of those Home Depot 5 gal buckets with barbs tapped into the side as my res / rad. CPU / GPU ran all day without reaching high temps.

Ben333 said:

Any fan will be MUCH better than no fans. So I'd recommend using fans wherever you can, just use ones your can't hear or under volt them. As said by others, PC radiators are designed specifically to be used with fans.

I once ran one of those Home Depot 5 gal buckets with barbs tapped into the side as my res / rad. CPU / GPU ran all day without reaching high temps.

Click to expand...

With an open-topped bucket like that I think you have quite a bit of surface area for the heat to escape the surface of the water.

caddi daddi said:

lenny, you are right, but with enough water acting as the heatsink you can go quite sometime before you need to bring the fans in.
as far as understanding, nobody had to, some folks just like to tinker around.

Click to expand...

Yep I get that - I've done plenty tinkering myself and will always do it because it's fun. But OP here is looking for direction and guidance rather than just sharing a tinkering project, and in his search for "good answers" there's simply no scope for supporting the idea of WC without fans. Had OP not asked question 2., I likely wouldn't have responded as I did.

build a solid aluminum desktop with a maze of channels running through it and 2 spots for water cooling tubes to go in and out. the whole table will be a passive heatsink.