[SOLVED] Got 5 fans, need help.

Solution
Actually, fans don't suck air. Fan blades are set for a specific pitch. When the blade moves, it moves the air under the blade forcing it out the back side under pressure (that's static pressure). Simultaneously, the displaced air creates a void, a vacuum, a low pressure area behind it. Nature abhors a vacuum and localized air will move to fill the space and equalize the pressure. Rinse and repeat for each blade moving across a certain area.

Some cases the fan is very close to the front glass, that provides a strong resistive force to outside air filling the fan, requires far more vacuum created to overcome the restriction. Move those fans back an inch and the vacuum gets stronger as it builds, so a lower rpm is all that's necessary...

Jubby

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Hi @Raz_5_ ,

The configuration with the arrows wouldn't be recommended. As the top right fan will pull air into the case then the front top fan will push it straight back out.

My current configuration is 3 pulling in from the front and 2 pushing out of the back. All 120mm fans. Maybe worth while testing temperatures with 2 on the front and the top right 1 pulling in then the exhaust and the top left pushing out.

Ideally you want pulling in from the right and pushing out to the left.

Remember your CPU cooler should also be pushing air to the exhaust as well. (presuming it's not an AIO)

Hope this helps.
 

Ferimer

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Can someone help me with my fans on which direction to go for optimal cooling? I have 5 to use. The front of the case is solid with little holes down the entire side with white plastic molds in them that I assume help with air movement out of those little holes.

Edit: The one with the arrows is what I'm thinking of doing.

View: http://imgur.com/gallery/nTh6vSf
Place 3 for intake on the Front. 1 on the rear for exhaust and another on Top Left for exhaust above the CPU. Essentially what you would be doing is Pushing all the hot air back and around. The GPU and if youre using an after market CPu Cooler you would just be pushing that hot air back and around again. You want to Push the Air towards an out not down towards your gpu and PSU. That will also create a negative pressure as you are going to be expelling more air out than in, causing more hot air to be trapped inside the case rather than cool air getting to components. The Cool air going in will just be sucked right out of the fans going left and right.
 
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Raz_5_

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Place 3 for intake on the Front. 1 on the rear for exhaust and another on Top Left for exhaust above the CPU. Essentially what you would be doing is Pushing all the hot air back and around. The GPU and if youre using an after market CPu Cooler you would just be pushing that hot air back and around again. You want to Push the Air towards an out not down towards your gpu and PSU. That will also create a negative pressure as you are going to be expelling more air out than in, causing more hot air to be trapped inside the case rather than cool air getting to components. The Cool air going in will just be sucked right out of the fans going left and right.

You think that's the best? Even tho the front of my case is solid and that it just has this side vent looking stuff
 

Raz_5_

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Place 3 for intake on the Front. 1 on the rear for exhaust and another on Top Left for exhaust above the CPU. Essentially what you would be doing is Pushing all the hot air back and around. The GPU and if youre using an after market CPu Cooler you would just be pushing that hot air back and around again. You want to Push the Air towards an out not down towards your gpu and PSU. That will also create a negative pressure as you are going to be expelling more air out than in, causing more hot air to be trapped inside the case rather than cool air getting to components. The Cool air going in will just be sucked right out of the fans going left and right.

Also I have a thing called the Shuriken Scythe 3 or whatever, a low profile CPU fan that sits on the CPU, so the air from that would be pushing against the side panel of my case.
 

Karadjgne

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Hot air rises. All your gpu exhaust heat wants to go UP. All your chipset, ram, cpu heat wants to go UP. Why would you the want to blow it all back into the case?

No. Your cpu cooler fan blows downwards, not outwards. The side of the fan you can see is the intake side, the exhaust side of the fan is the ugly side with the motor and wiring. Air gets blown into the heatsink, towards the motherboard, not toward the side of the case.

You cpu cooler is a downdraft broadcast cooler, not a tower. Your best bet is either 3 in front, 2 on top (rear most ports) or 2 in front (lowest ports) and 3 on top. Block off any unused ports. Id not use the rear exhaust as that only confuses airflow to the cpu cooler, stealing its air so to speak.
 

Ferimer

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You think that's the best? Even tho the front of my case is solid and that it just has this side vent looking stuff
Fans SUCK air in. SO no matter what as long as you have air in the general area of your computer it will get air. Mind you it wont as much as say a front mesh panel, however with 3 fans tuned to rotate a little bit faster in the bios settings you can suck more in. I would say have them going at like a constant 50% or whatever you feel is more quiet level that you prefer. As pointed out by Karadjgne hot air always wants to go up as its less dense than cool air meaning that cool air stays lower. Having the hot air from above the case and what is being expelled by both CPU and GPU fans you are going to be pushing that hot air right back in to the GPU and the PSU. you want the intake fans to come from under the PSU and the GPU so that it gets force up faster and out causing it to be cooler inside.
 

Karadjgne

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Actually, fans don't suck air. Fan blades are set for a specific pitch. When the blade moves, it moves the air under the blade forcing it out the back side under pressure (that's static pressure). Simultaneously, the displaced air creates a void, a vacuum, a low pressure area behind it. Nature abhors a vacuum and localized air will move to fill the space and equalize the pressure. Rinse and repeat for each blade moving across a certain area.

Some cases the fan is very close to the front glass, that provides a strong resistive force to outside air filling the fan, requires far more vacuum created to overcome the restriction. Move those fans back an inch and the vacuum gets stronger as it builds, so a lower rpm is all that's necessary.

Ppl running sli ran onto this all the time. It wasn't heat generated that made the top gpu run hotter, you could use blower designs or axial and get the same results. It's the fact of the distance between the gpus restricted airflow to the point where even at max fan speeds the fan simply couldn't create enough vacuum to overcome such a small gap. Like trying to suck juice through a coffee stirrer vs a McDonald's straw.
 
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Solution
Can someone help me with my fans on which direction to go for optimal cooling?
This is pretty much golden standard for air flow:

png-clipart-computer-cases-housings-power-supply-unit-corsair-components-atx-overclocking-airflow-electronics-electronic-device.png
 

HWOC

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What SkyNetRising said. This question gets asked on the internet about 1 gazillion times per day, if we could somehow post the above picture across the globe on all billboards, it would save a lot of people a lot of time. 🆒
 

Karadjgne

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Ahh, but that's where things get trixy, assuming that that airflow picture is a one-size-fits all. It's far from it.

The nzxt H510 series is quite popular. The picture is wrong. Best overall temps are achieved by simply using 2x exhaust fans. No intakes at all.

Downdraft/broadcast type coolers don't require a rear exhaust, often do better without.

Top mounted AIO's. Don't require a rear exhaust. Better to block that hole up and make the case 'chimney'.

There's more than a few cases and cooler styles where that picture isn't optimal. It might be the Golden Standard, cover a very large chunk of cases, but it's far from Gospel.
 

Karadjgne

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'My case is Special. It says it's designed for performance airflow, has 9 fan slots, tons of rgb, TG, so it cannot be just like everyone else's plain black box.'

'hmm, can't see the RGB if I put the fan that way, so it must go the other way.'

'I have every fan slot filled, why am I getting high temps, higher than my friend who only has 4 fans so much worse airflow'.

And the list goes on.....
 

Karadjgne

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Hmm, you'd think so, but not quite.

Go to McDonald's and buy a soda. Stick a straw in it. Suck on the straw, you get soda in your mouth. Perfect.

Now put a hole in the straw above the soda. Suck on the straw and you get nothing but air, maybe a little dribble of soda.

That's a rear exhaust as a passive intake. That top/rear aio fan will be pulling fresh air directly from that vent. Yes your cpu temps will be a few °C lower, you've got a source of colder air very close to the fan, but the byproduct is less draw of case air from above the gpu. If you keep the aio fans higher rpm, that's going to minimize that affect, the gpu exhaust will be directed more towards the front aio fan, but overall after a longer gpu exhaust period, the affect on the gpu will be higher temps as the case air is more stagnant.

With GPU Boost boosting according to temps, you'll end up with a smaller boost, worse speeds and performance, same gpu temp reading.

It's the nzxt H510 affect from a different angle. Changing airflow patterns.
 

Karadjgne

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Lol 🤣.
True, that really only applies to aircooling. Which is 98% of gpus.
Being full custom loop or aio cooled, airflow isn't a priority in any sense, just need air through the rads.

AirFLOW works best as a single, directed channel, in then out. The more confusticated it gets with opposing angles, the more stagnant it gets, creating Hotspots. Just have to decide on priorities, most ppl think the cpu must always be the highest priority, run the coolest possible, and thats often a mistake as it puts strain on the rest of the pc, which can lead to lowered performance. No point in a 50°C cpu if the Sata chipset is at 100°C when the same cpu at 53°C means the Sata chipset is running at 80°C.
 
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