Can you ever have to much radiator capacity?

Associate
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I have tried 8 fans and up to 21 fans in push pull config. push pull made no difference in temp. but all the fans did not make any different in noise either. i am running corsair SP120 quiet editions and run them at 35% fan speed using a fan controller.

IF PWM fans are used i am certain acoustics level can even be better.

Custom water is never cheap. People do it because of better overclocking/cooling/acoustics/looks.

If you get a decent pump like a D5 that will pretty much run most loops.
 
Soldato
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Most radiators are not very restrictive.
Yea rads are not that restrictive. I was surprised when flushing it how easy flow can pass through. It's just cpu and gpu blocks which seem to restrict flow. obviously more blocks you have will increase pressure slightly but nothing compared to adding a second gpu and block.

@ OP Best you could expect from an extra 120mm rad space is to reduce fan speeds slightly to reduce noise. Could help with keeping fluid temps down 1-2 degrees at best case. 480mm of rad space is enough for a CPU and GPU only loop easily with big overclocks.
 
Soldato
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Of course, I see your point, but fans only run so slow, and it's not like you can keep ratcheting fan speed down relative to quantity of fans... eventually you hit a bottom speed limit (400-600RPM typically, depending on the fan in question, some will be higher). For example, for fans running at 600RPM, x12 of them are going to emit more noise than x8. That's just obvious, they aren't totally silent. How much noise will depend on the fan of course, and it may be negligible in some instances to the point that it isn't really noticeable. Every set-up will be different. Ultimately though, it's pointless beyond a certain number, especially when you factor in cost/performance.
That is true, but the sound of fans doesn't increase in a linear fashion. For example 4 fans aren't twice as loud as 2 fans. So it's very possible that there wouldn't be a perceivable difference in volume going from 8 go 12 fans if they're well performing at low RPM.
 
Soldato
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That is true, but the sound of fans doesn't increase in a linear fashion. For example 4 fans aren't twice as loud as 2 fans. So it's very possible that there wouldn't be a perceivable difference in volume going from 8 go 12 fans if they're well performing at low RPM.


True. As I say, all depends on the fans in question. May not be much difference in some instances, but regardless, once you get beyond a certain point, you're looking at a lousy price/performance result when spending over £100 on an extra rad and fans (as you would do with any 360+ rad with a decent set of fans).
 
Soldato
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This is a handy calculator for working out noise levels when adding more sources. The more you add of the same noise level the less overall effect it has.

http://www.sengpielaudio.com/calculator-spl.htm


Interesting. Less effect, but that obviously doesn't mean 20 fans would be quieter than 10. You're still going to get a cumulative build up, but I see from the maths that the noise would not scale linearly. The location of fans in a build also can be a factor. I've had that before where one fan was more noticeable than another, perhaps just because of its location in the case and how the airflow around it was being impacted in some way by the case structure or a nearby component. Every build will be different. Ultimately it will simply come down to how much someone wants to spend and how much value and priority they put on every single degree and decibel. Fun to experiment with this kind of stuff I guess.
 
Soldato
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Interesting. Less effect, but that obviously doesn't mean 20 fans would be quieter than 10.


Well yes it can if these fans are spinning slower, it all depends on the speed of the fan.

example:

3 fans @ 15dB = 19.77dB

6 fans @ 10dB = 17.78dB
9 fans @ 10dB = 19.54dB
10 fans @ 10dB = 19.99dB

So you can have more than 3 times the amount of fans and basically the same dB rating.

I have gone from a single 480mm radiator to a 480mm and 420mm radiator setup and my water temps have dropped as has the noise levels. Even though I have more fans the fan speeds are lower. It really all depends on how you set up the loop and what you are trying to achieve.

You are correct that a position/location of a fan can very much effect noise levels too, there really are many things to take into account when trying to get the lowest noise levels possible. I see setting up a loop for noise levels a bit like an onion and its many layers, reduce one sound source and there is another waiting to be dealt with. Its not cheap and can take a fair amount of time balancing everything out but as you say its fun to experiment, at least I enjoy it. :)
 
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Associate
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big enough loop (external ) will cool itself as long as you keep the big box (room) cool. higher flow pump with bigger tubing as opposed to higher pressure rated. water pressure is .52 psi /ft static+/-. pretty much to over come head pressure but in a closed loop that doesn't really matter. you only need to overcome resistance to flow in your system which is minimal. afaik. so huge rads dissipate better as long as they create minimal resistance to flow. as your in rad water time is longer. while fast flow over blocks removes more heat from the cpu/gpu block or whatever you want to cool. to need higher pressure normally shows restrictive flow. ala finger over hose pipe.
 
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