# What do you recommend for fan setup?



## Lulubermudez (Dec 9, 2020)

It's my first pc build and I'm planning to add 3 extra 120mm fans to my Phanteks Elipse P300 (not P300A). I was planning to add two intake in the front but I'm wondering if the one at the top should be intake or escape. I know it's normally escape, but this case has a dust filter at the top that I feel would be unused if left for escape. Could two front and 1 top intake, and 1 back escape work fine for me? Below my specs:

AMD Ryzen 5 3600XT (w/ stock cooler)
MSI Radeon RX 5500 XT 8GB Gaming X
MSI B450 Tomahawk Max
T-FORCE VULCAN Z 16GB (8GBx2) 3000Mhz CL16
GIGABYTE 128MB SSD M.2
SAMSUNG 1TB SSD SATAIII
Be quiet! 80+Bronce 600W non modular

Clearly not planning on OC until I get a decent CPU cooler.


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## Deleted member 24505 (Dec 9, 2020)

i would still go 2 front in, top out back out to balance it. I have a phanteks xvolv x and have 3 140 front in, 2 140 top out and 1 140 rear out.


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## NoJuan999 (Dec 9, 2020)

Hot air rises so you want to use the top as exhaust.
I have 3 120mm front intakes and 140mm top and 120mm and 80mm rear as exhaust and my case has excellent airflow.


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## maxfly (Dec 9, 2020)

Try the top fan both ways. As an exhaust and then test it as an inlet. If your aircooling you may find that one is going to give you better cpu temps vs the other.


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## OrlyP (Dec 9, 2020)

For your case, it's easier.... both the rear and top fans should be exhaust.

For cases that can accomodate 2 or 3 top-mount fans, the fan nearest the front should be inlet, while the one nearest the back should be exhaust.

Gamers Nexus has provided a very detailed comparison on thermals for different fan positions and directions. They also covered why "hot air rises up" does not really apply in PC cases when there's airflow involved.


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## DeathtoGnomes (Dec 9, 2020)

maxfly said:


> Try the top fan both ways. As an exhaust and then test it as an inlet.


No. Top inlet is minimal difference in airflow, since, as said, heat rises. A single top intake fan would be working against itself. Optimal configuration is following a fan-for-fan method, equal intake and exhaust fans, with extra intakes in the front if available/needed.


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## OrlyP (Dec 9, 2020)

Just to reiterate, "hot air rises up" does not apply here or is negligible if you already have front-to-back airflow through the case. 

Speaking strictly about *top-of-case* fan placements and direction, particularly if you have a tower cooler, top-rear should be blowing out while top-front (if there's a cut-out and you care to put a fan in there) should be blowing in.

Doing so, the top-front fan can complement the front fans, blowing fresh outside air into the tower cooler.

Both the rear and the top-rear fans should be blowing out to expel heat generated by the tower cooler and VRMs, among others.

Some visualization and explanation from Steve.... *Skip to the 7:40 mark:*


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## EarthDog (Dec 9, 2020)

In most chassis... front/sides = intake, top/rear = exhaust.

Want to know about dust and pos/neg pressure? It doesn't matter as much as people think...... 









						Dust Prevention and Case Pressure: Does It Really Matter? - Overclockers
					

Overclockers has teamed up with be quiet! to conduct the first physical testing as to whether positive case pressure really does reduce dust in your PC.




					www.overclockers.com
				






maxfly said:


> pressure it moves which ever way the case fans are creating the most pressure


pressure, in something that isn't sealed, is negligble. Airflow I think is what you are looking for.


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## maxfly (Dec 9, 2020)

DeathtoGnomes said:


> No. Top inlet is minimal difference in airflow, since, as said, heat rises. A single top intake fan would be working against itself. Optimal configuration is following a fan-for-fan method, equal intake and exhaust fans, with extra intakes in the front if available/needed.



No. Heat rises in a static environment. In a computer case with fans creating pressure it moves which ever way the case fans are creating the most pressure. If OP were running a single top intake they would be feeding the heatsink cool external air rather than battling this loathesome overpowering rising heat lol. Optimal configuration is in the eye of the beholder. It certainly isnt set on stone. Rather its more a case by case or personal taste endeavor. Some prefer positive, some negative.
My suggestion was for the OP to simply try the top fan either way once the other fans have been installed so that they can see for themselves what the differences may or may not be. Simple.


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## dirtyferret (Dec 9, 2020)

Heat does not rise, heat spreads to cooler areas.  Hot air will rise but slowly and will go in whatever direction your fan pushes it.



Lulubermudez said:


> It's my first pc build and I'm planning to add 3 extra 120mm fans to my Phanteks Elipse P300 (not P300A). I was planning to add two intake in the front but I'm wondering if the one at the top should be intake or escape. I know it's normally escape, but this case has a dust filter at the top that I feel would be unused if left for escape. Could two front and 1 top intake, and 1 back escape work fine for me? Below my specs:
> 
> AMD Ryzen 5 3600XT (w/ stock cooler)
> MSI Radeon RX 5500 XT 8GB Gaming X
> ...


I own both the phanteks P400s and P400A.  Using an air cooler, use two intake fans up front, one exhaust in the rear and one exhaust in the top back panel.  Leave the top front open so the air cooler can pull in outside air (leave the mesh filter on the panel)


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## ThrashZone (Dec 9, 2020)

Hi,
I do top and front intake yes they are also by design screen filtered I add my own filtering too old of old speaker cloth I had laying around does a better job than the screens do at catching micro dust.
I have no exhaust fans at all since the rear of the case is open and all air is forced out the back naturally.


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## DeathtoGnomes (Dec 9, 2020)

dirtyferret said:


> Heat does not rise,


Laws of Thermodynamics be damned? What planet are you from?



dirtyferret said:


> Hot air will rise


Hot air = heated air = Heat 



maxfly said:


> In a computer case with fans creating pressure it moves which ever way the case fans are creating the most pressure. If OP were running a single top intake they would be feeding the heatsink cool external air rather than battling this loathesome overpowering rising heat lol


The first sentence is almost correct, that is until you creat higher pressures than the air loses some flow.
B. I never said overpowering, embellishing what I said is akin to saying the sky is falling.



dirtyferret said:


> Leave the top front open so the air cooler can pull in outside air (leave the mesh filter on the panel)


This makes no sense and defeats the purpose of installing front intake fans. If there is positive case pressure, airflow will follow the path of least resistance, meaning if the top fans cant pull the air out the air will exhaust in that port. Not that that will actually happen with a smart fan config.


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## Lulubermudez (Dec 9, 2020)

Thanks all for your help! It makes sense to do front in, top and back out, but my pseudo OCD hurts when I think there's a dust filter in the only top fan nd I'm using it as out. I'll still probably do out on it and rely on the front and down (PSU) dust filters. Thanks again!


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## DeathtoGnomes (Dec 9, 2020)

Lulubermudez said:


> Thanks all for your help! It makes sense to do front in, top and back out, but my pseudo OCD hurts when I think there's a dust filter in the only top fan nd I'm using it as out. I'll still probably do out on it and rely on the front and down (PSU) dust filters. Thanks again!




( The top dust filter is there for when there is no top fans installed )


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## EarthDog (Dec 9, 2020)

Lulubermudez said:


> Thanks all for your help! It makes sense to do front in, top and back out, but my pseudo OCD hurts when I think there's a dust filter in the only top fan nd I'm using it as out. I'll still probably do out on it and rely on the front and down (PSU) dust filters. Thanks again!


Remove the filter up top if it is exhaust...


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## Chrispy_ (Dec 9, 2020)

This is a no-brainer.

The case is designed for two intakes at the front and two exhausts (one top, one rear).

If it were me I'd get 140mm fans for the front so that you effectively seal the gaps in the frame and maximise their intake. With 120mm fans and those fairly small intakes at the top and bottom of the front panel, there will be very low pressure in that front panel void and a lot of airflow will simply roll around the frame and go back into that void, wasting some of the airflow as recirculation.

If you only have 120mm fans, you can just tape over the gap instead, but 140mm fans is a more elegant solution.


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## ThrashZone (Dec 9, 2020)

Hi,
lol the only item I would remove are the pci-e slot covers that block air from exiting out the back easier


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## EarthDog (Dec 9, 2020)

ThrashZone said:


> Hi,
> lol the only item I would remove are the pci-e slot covers that block air from exiting out the back easier


You don't want to do that, generally, as it disrupts airFLOW. The key to removing heat is airFLOW. You want it to follow the fan 'path/flow direction as much as you can. This is really counter intuitive with more exhaust CFM than intake as it take air in from there only to be immediately removed. You want the fans to take the heat inside and move it out while not disrupting flow.


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## dirtyferret (Dec 9, 2020)

DeathtoGnomes said:


> Laws of Thermodynamics be damned? What planet are you from?


You want to discuss science by ignoring science?....



DeathtoGnomes said:


> Hot air = heated air = Heat


I'm not sure of your education but you are wrong, perhaps less hitting your head.

The best description I have ever read of the difference;

_Hot air is not heat, it's not the same thing.

Heat is transmitted in three different ways: conduction, convection, and radiation. Conduction happens when two bodies with different temperatures make contact. In the contact surface, heat flows from the hot to the cold body.

Radiation is the emission of electromagnetic radiation with wave length related to the temperature of the body. All bodies emits this radiation.

Convection happens when the hot body and the cold body are separated by a fluid. The hot body warms the fluid and the fluid normally moves up, as it's density is lower. Eventually it will make contact with the cold body and heat it. The only exception for the density thing is the water, that is less dense when temperature is between 5ºC and 0ºC, that's why lakes froze from top to bottom and not the opposite._



DeathtoGnomes said:


> This makes no sense and defeats the purpose of installing front intake fans. If there is positive case pressure, airflow will follow the path of least resistance, meaning if the top fans cant pull the air out the air will exhaust in that port. Not that that will actually happen with a smart fan config.



So this is obviously a difficult thing to discus with someone who fails to understand the basic difference of heat and hot air but here is the explanation via bit- tech (GN has come to the same conclusion).

_As a result of this we’re able to fashion some simple air cooling principles which hopefully should be relevant to most builds and, as long as case design doesn’t change radically in the next few years, remain relevant for your next build too._


_
*1.* The amount of venting in your case can have a huge impact on cooling, particularly around the CPU area. If you have fan mounts here that are blocked up, unblock them.

*2.* Generally, all other things being equal, it’s better to get hot air out of your case than to pump cool air in, particularly when it comes to CPU cooling.

*3.* If you have a roof mount that’s located nearer the front of the case than the CPU cooler, leave it open. Fitting a fan here only causes problems.

*4.* If you have one, two or three fans in your case, the side panel intake mount is the most important. Fill this first, followed by the rear exhaust mount, followed by the roof exhaust mount.

*5.* Bear in mind the fact that fans have an effect on each other and use this to your advantage. For this to work though they need to be close enough to interact - a side intake works better with a rear exhaust than a front intake does for this reason.

*6.* With four or more fans, concentrate on traditional front to back cooling and creating one strong, continuous air flow. Fill the front intakes and the roof and rear exhausts first.

*7.* More fans does mean more cooling, but expect diminishing ret_urns when going above three or four fans


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## freeagent (Dec 9, 2020)

Case flow should move front to back. Top exhaust brings GPU heat up to CPU cooler and VRM's. Top exhaust negates having a front fan as it draws the air out before it can actually make it to the CPU cooler or anything else. If you cant get the warm air out fast enough best to have more intake to cool and push the warm air out to avoid the hotbox effect. Just my opinion.. works well for me. If you have a case that doesn't flow well, then you have a pretty case. I use thick fans so airflow is never a problem, especially in a tiny case like a Meshify C.


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## Lulubermudez (Dec 9, 2020)

freeagent said:


> Case flow should move front to back. Top exhaust brings GPU heat up to CPU cooler and VRM's. Top exhaust negates having a front fan as it draws the air out before it can actually make it to the CPU cooler or anything else. If you cant get the warm air out fast enough best to have more intake to cool and push the warm air out to avoid the hotbox effect. Just my opinion.. works well for me. If you have a case that doesn't flow well, then you have a pretty case. I use thick fans so airflow is never a problem, especially in a tiny case like a Meshify C.


 So what you'r saying is that I should only use two fron intake and one back out and leave the top without a fan at all??


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## EarthDog (Dec 9, 2020)

Lulubermudez said:


> So what you'r saying is that I should only use two fron intake and one back out and leave the top without a fan at all??


Brotha, as you can see, there are as many opinions about this subject as there are people, lol. Some advice goes against the grain and is a preference or it actually works better in their chassis.

You really need to try it yourself and see what works best for you. The difference between most of these setups are only a couple/few C and not worth digging into the minutia (for me). If you want to play around and test, just be sure your testing is empirical and repeatable. Room temp needs to stay the same or be accounted for... same test, test length, etc...

But generally, you want front/sides as intake and top/rear as exhaust. I've ALWAYS used an exhaust fan on the rear or top where I can.


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## NoJuan999 (Dec 9, 2020)

EarthDog said:


> Brotha, as you can see, there are as many opinions about this subject as there are people, lol. Some advice goes against the grain and is a preference or it actually works better in their chassis.
> 
> You really need to try it yourself and see what works best for you. The difference between most of these setups are only a couple/few C and not worth digging into the minutia (for me). If you want to play around and test, just be sure your testing is empirical and repeatable. Room temp needs to stay the same or be accounted for... same test, test length, etc...
> 
> But generally, you want front/sides as intake and top/rear as exhaust. I've ALWAYS used an exhaust fan on the rear or top where I can.


Exactly.
Try it and see what works best in Your case.

I have always set up my fans like that as well, front and side panel (if there is one) fans as intake and top/rear as exhaust.
I have never had a problem and my PCs always run fairly cool.

In my current rig (3700x / 2060 Super) the CPU idles at around 32-34 and maxes out around 60-65c while gaming/encoding videos. The GPU idles around 34C and maxes out around 62-65C.


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## c2DDragon (Dec 9, 2020)

I'm doing front in, rear out. I don't use fans on top anymore because of the dust and the sound added. The more you use fans, the more you get noise. I like silence 
You won't win 15°C adding 3 fans (if you already have at least 1 rear fan on the case of course).
I guess you could test with 1 front, 1 rear, watch your temps after an intensive compute/gaming session then add a second front fan and see. If noise & vibrations are not a problem for you, go yolo and add everything you can, I doubt you will be satisfied to be honest


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## freeagent (Dec 9, 2020)

Lulubermudez said:


> So what you'r saying is that I should only use two fron intake and one back out and leave the top without a fan at all??


In my Meshify C, though not right now.. I use the very top front as another intake to feed my cpu fan and cool my ram and to keep the air from the fronts from going right out the top. Behind my cooler at the top I use another exhaust. People would say I am making a warm air loop like that.. but it’s not because so much air is moving. So in my Meshify C when it’s all done up I have 4x 120x38s intake, 2x 120x38s exhaust, and a 92x35 under my GPU exhausting out the back for a grand total of 4 in 3 out. Some would say it’s excessive, maybe..


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## DeathtoGnomes (Dec 10, 2020)

dirtyferret said:


> I'm not sure of your education but you are wrong, perhaps less hitting your head.


there's no call for personal attacks.


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## dirtyferret (Dec 10, 2020)

DeathtoGnomes said:


> there's no call for personal attacks.


you are right my apologies


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