[SOLVED] 3 exhaust fans , 2 intake? Is it okay?

manosklg

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Hello guys. So im about to build my first ever gaming pc in the Meshify C Dark TG case. Its an amazing case for airflow as Ive seen from reviews but Im a bit confused on the way airflow works. The case comes with 1 fan installed in the front as intake and one in the far back as exhaust. Both 120mm. I will be removing the exhaust fan and will place it in the front to have 2 intakes. Also, I will put in the build 3x corsair ll120 rgb fans. One in the back as exhaust and two at the top, as exhaust again. So:
3 exhaust fans (2 top, 1 back)
2 intake fans (2 front).

Is this okay? Am I supposed to have more intake fans than exhaust ones? Will it be better if one at the top is exhaust and one is intake? Please let me know. Im a noob to all this haha.
I will be using the Ryzen 5 3600X as cpu and the RX 6800 gaming oc as gpu. Im not 100% sure if this will require a different setup of airflow
Thank you!
 
Solution
Neutral pressure is fine, kind of hard to achieve usually. Typically your intake fans are filtered and exhaust fans not. So with equal fans you always expect some negative pressure.

About the only way would be to reduce the fan speeds on the exhaust, but to be sure you would have to do a smoke test or the like to see if air was going in or out around gaps.

With mismatched fans, not sure. Would depend on the RPM/CFM of the fans in question.

As Colif states, as long as you are diligent about maintenance, it doesn't really matter. I clean my HTPC about 4-6 times a year since it sits on the floor, vacuum the front every time I vacuum. My gaming PC sees less use these days, clean it semi-annually and top off the fluids.

Eximo

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It is an okay layout for cooling, and fits the layout of the case.

Only downside to having more exhaust than intake is that if there is enough negative pressure, air will get in at places other than the intake. Might cause a build up of dust in those locations. Intakes are filtered, so almost certainly they are working harder than the exhaust fans.

When you have more intake than exhaust you get positive pressure, which will push air out at any gaps in the case, meaning all incoming air is filtered.
 
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manosklg

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It is an okay layout for cooling, and fits the layout of the case.

Only downside to having more exhaust than intake is that if there is enough negative pressure, air will get in at places other than the intake. Might cause a build up of dust in those locations. Intakes are filtered, so almost certainly they are working harder than the exhaust fans.

When you have more intake than exhaust you get positive pressure, which will push air out at any gaps in the case, meaning all incoming air is filtered.
I see. So the best fan layout for this case would be 3 intake in the front, 1 exhaust at the back and 1 exhaust at the top back?

What about ''neutral'' pressure? I have another fan that I bought few months ago but didnt end up using it. Its a Be Quiet SilentWings 3. What if I have 3 intake in the front, 1 exhaust at the back and 2 exhaust at the top?
 

Colif

Win 11 Master
Moderator
3 exhaust fans (2 top, 1 back)
2 intake fans (2 front).
that is my set up in a Meshify S2, I can agree you will get some dust but its not so bad, just have to clean top mesh every few weeks but that depends how dusty room is - mine needs a clean. It is possible to remove the mesh but it acts as a barrier to stop dust falling into pc from above, so I left it in.

Had PC 6 months, haven't really needed to clean inside PC at all, once maybe, apart from the glass. Difficult to get front off, so not sure what filter is like there. Dust has to be pulled through my AIO at front, to get into case that way anyway.
 
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Eximo

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Neutral pressure is fine, kind of hard to achieve usually. Typically your intake fans are filtered and exhaust fans not. So with equal fans you always expect some negative pressure.

About the only way would be to reduce the fan speeds on the exhaust, but to be sure you would have to do a smoke test or the like to see if air was going in or out around gaps.

With mismatched fans, not sure. Would depend on the RPM/CFM of the fans in question.

As Colif states, as long as you are diligent about maintenance, it doesn't really matter. I clean my HTPC about 4-6 times a year since it sits on the floor, vacuum the front every time I vacuum. My gaming PC sees less use these days, clean it semi-annually and top off the fluids.
 
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Solution

Colif

Win 11 Master
Moderator
i have 2 x 120mm intake & 3 x 140mm exhausts, so I have no hope of neutral or positive, even if I remove 1 exhaust its still uneven. I wonder if having negative means there is less chance of dust on the intake filters since air will try to get in other non filtered places. Just wondering as not sure if I ever seen any on intake filters.

I need to properly clean the TG, the inner adhesive left some residue and dust likes to stick to it. I can also feel it on outside too. But as its behind the RGB fans of AIO I can't really see it unless I look hard, or take a photo. Camera always sees the dust I can't
 
A very nice case.
What parts will you have inside that you need to cool?

The basic principle of cooling is to have fresh/cool air enter the system, collect heat from components, and send the heat out of the case.

Whatever fresh air enters the system will eventually exit the system, taking component heat with it.
This is not a pressure constrained system like a food pressure cooker where heat can build up.

A second principle is that if all the intake air is from one source, and is filtered, dust will not make it's way to your parts.
This is called a positive pressure system.
You may never need to clean the interior of your case.

Your case has provision for two 140mm intakes or three 120mm intakes.
Either setup has about the same intake area.
Either would work.
I would favor using two 140mm font intakes.
140mm fans turn slower and will be quieter.
You can get them in any speed, and Noctua makes some of the best and quietest. $20 each for two 140mm fans.

I would leave the 120mm rear fan where it is.
The main reason for a rear exhaust is to direct the airflow over the motherboard, graphics card and cpu cooler.

Just because you have an extra ran, do not bother to mount it on top as an exhaust.
Doing so will tend to draw in unfiltered air from adjacent openings.
It will also tend to divert the cooling airflow to exit the case without passing over any parts.

A good tower type air cooler will do the job, even with the strongest of processors.

If you are an overclocker, seeking record overclocks from a high powered cpu, this case is not for you.
You would need a case capable of installing a 360 aio to do any better.
Today, processors and motherboards use turbo mechanisms to provide peak cpu performance on a few favored cores when you need it. Overclocking is no longer a way to get something for nothing.
 

Windows22

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Neutral pressure is fine, kind of hard to achieve usually. Typically your intake fans are filtered and exhaust fans not. So with equal fans you always expect some negative pressure.

About the only way would be to reduce the fan speeds on the exhaust, but to be sure you would have to do a smoke test or the like to see if air was going in or out around gaps.

With mismatched fans, not sure. Would depend on the RPM/CFM of the fans in question.

As Colif states, as long as you are diligent about maintenance, it doesn't really matter. I clean my HTPC about 4-6 times a year since it sits on the floor, vacuum the front every time I vacuum. My gaming PC sees less use these days, clean it semi-annually and top off the fluids.
I agree with this tact.