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How to know the case fan is input/ouput?

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Aug 16, 2020
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System Name look here
Processor AMD Ryzen 5 3600
Motherboard MSI MAG B550 TOMAHAWK
Cooling be quite
Memory g.skil ripjaws v series
Video Card(s) MSI GeForce GTX 1660 SUPER
Storage Western Digital Blue 500 GB M.2-2280
Case phanteks eclipse p400a
Power Supply SeaSonic FOCUS Plus Gold 650 W 80+ Gold
My question as topic, which ways should be input, otherviews is output?

I searched the information and didn't understand.
 
I'm assuming you're asking about fan airflow direction (intake/exhaust). Nowadays all consumer mainstream fans follow the same method. The fans back grill side exhausts air and the front open side intakes air .

eg. if you had the following sides facing you:

- front open side: the air would blow away from you (intake)

fanfront.jpg


- Back Grill side (below): the air would blow towards you (exhaust)


fanorientation.jpg


If its still confusing... I see you have the P400A case. The front fans work best as intakes and the top and rear fans work best as exhausts. The finished product should resemble something like this: https://cdna.pcpartpicker.com/stati...266.6bfcb59088da17e2482f534249187852.1600.jpg
 
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Most fans I have encountered have direction arrows on them.
For fan rotation direction and air flow direction.
^^^This^^^ (assuming you are asking how to tell which way a fan spins).

My question as topic, which ways should be input, otherviews is output?

However, if you are asking which way you should mount the fan (as exhaust or intake), the goal is to create a nice "flow" of air through the case so cool air is pushed into the case and heated air is exhausted out. You want all the fans to work together to create that desired flow - not against each other. The common setup is to have fans in front as intake (hopefully pulling air in through filters), and fans in the back as exhaust.

You certainly can have rear fans as intake and front as exhaust - that just is not common. And if the case has filters, they typically are mounted in front to filter the air coming in. Also, PSUs typically exhaust out the back already too.

Some cases support bottom fans and they typically are intake. And some cases have "blowhole" (top) fans and they typically exhaust air out. However, when a radiator for water cooling is mounted up top, those often are intakes that rely on rear fans to exhaust the heated air out.

Cases with bottom mounted fans that blow into a dedicated compartment/chamber where the PSU is mounted typically don't affect case cooling - but still typically channel the PSUs heated air out the back.

Regardless, I recommend using a HW monitor to keep watch on your temps. And for that, I use and recommend Core Temp to monitor CPU temps in real time. Under Options > Settings > Notification Area, I have mine set to display "Highest temperature" only.
 
You can always use the old fashioned trick of turning the system on and feeling the direction of airflow with your hand o_O
 
Low quality post by eidairaman1
My question as topic, which ways should be input, otherviews is output?

I searched the information and didn't understand.
There are plenty of youtube videos on this, go find them.
 
^^ This, as there are some that are reversed.

Purposely, and paired with one or two others which you'd imagine are usually kept together.
 
I checked and reserached the information on Youtube. Two tips help me understand it.
1. use the tissue paper closing to the case fan
2. see the arrow on the fan side

thanks for help here:toast:
 
I checked and reserached the information on Youtube. Two tips help me understand it.
1. use the tissue paper closing to the case fan
2. see the arrow on the fan side

thanks for help here:toast:
Still this requires a spinning fan and/or searching for arrows that may or may not exist. There are more simple ways.

1. The fan motor mount brackets are always to the side of which the air is leaving the fan(exhaust side).
2. Fan blades on 99.9% of PC case fans are curved. The outside of curvature is intake and the inside is exhaust.
 
"More" simple ways than looking for arrows? Nah! Not even.

"IF" there are no arrows and/or spare PSU connector handy, then those are viable, alternative methods. But for sure, the easiest way, by far, is to simply look! Odds are, there will be direction indicators on the fan housing. No need to remember if the bracket on this side, or that side means intake or exhaust. No need to determine which side of a blade is the inside or outside of fan blade, or what that even suggests.

Is it possible a fan will not have direction arrows? Of course! Just as it is possible, contrary to your absolute, blanket statement, the mounting bracket might be on the intake side of a fan.

Below is a picture I just took of a bunch of random fans I just pulled out from my box of spare fans. While you will have to take my word for it, I assure you, they all have direction arrows embossed in their housings.
 

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Any suggestions for the case fans? Which brands? Which model?
 
Below is a picture I just took of a bunch of random fans I just pulled out from my box of spare fans. While you will have to take my word for it, I assure you, they all have direction arrows embossed in their housings.
You might be right about the arrows. I never even notice them or look for them.

BTW I can tell from that picture what side is intake/exhaust of every single fan.
 
Any suggestions for the case fans? Which brands? Which model?
This will be a never ending discussion with more questions than you expect
The type of case you use, how you're powering them, are they being used in a case with low or high airflow restriction, etc etc


You're better off showing us where you want it to be used, and then listing fans you can buy in your price range wherever in the world you are - give us a shortlist to work with
 
BTW I can tell from that picture what side is intake/exhaust of every single fan.
So can I. But I never assume everyone else has a trained eye, or the experience with electronics, or fans, to know what to look for.
 
So can I. But I never assume everyone else has a trained eye, or the experience with electronics, or fans, to know what to look for.
No doubt you can. I know you in here.
Was trying to get OP and maybe as many as possible to able to do so too.

My mistake was to call that simpler way. It is to me and you apparently.

I believe (probably you too) that you only know something truly when you know how it works and why its made the way it is.
 
My mistake was to call that simpler way. It is to me and you apparently.
No, not me. For one, I do not assume rotation direction can ALWAYS be determined by looking at the mounting bracket. Some fans, for example, are reversable. A ceiling fan might be a perfect example. Or a window fan. And then, of course, there are reverse flow computer case fans too.

So for me, again, the simpler way is to look at the direction indicators [hopefully] embossed on the housing.

I believe (probably you too) that you only know something truly when you know how it works and why its made the way it is.
The mistake there is assuming what you know to be true with "this", automatically makes it true with "that".
 
No, not me. For one, I do not assume rotation direction can ALWAYS be determined by looking at the mounting bracket. Some fans, for example, are reversable. A ceiling fan might be a perfect example. Or a window fan. And then, of course, there are reverse flow computer case fans too.

So for me, again, the simpler way is to look at the direction indicators [hopefully] embossed on the housing.


The mistake there is assuming what you know to be true with "this", automatically makes it true with "that".
Ok, your arguments here involve totally irrelevant products, like ceilling/window fan that we do not discuss here. I didnt say all fans in the world are made in a certain way. Dont put words on my keyboard please.
Still its not a mistake to say that PC case fans always have a direction of air flow towards the motor brackets... and I can add... unless told otherwise (reverse flow right on the name of it).
Apparently there is a reason why they had to put "reverse" on the product name and description.
 
Ok, your arguments here involve totally irrelevant products, like ceilling/window fan that we do not discuss here. I didnt say all fans in the world are made in a certain way. Dont put words on my keyboard please.
Still its not a mistake to say that PC case fans always have a direction of air flow towards the motor brackets... and I can add... unless told otherwise (reverse flow right on the name of it).
Apparently there is a reason why they had to put "reverse" on the product name and description.
It's amazing how far people will go to avoid admitting they made a simple, no-big-deal, mistake. And instead of doing so, they just dig themselves in deeper. :kookoo:

No, you didn't specifically say "all fans in the world". You just implied that by saying, said, "fan motor mount brackets are always to the... ...exhaust side." You didn't say "most" brackets. You just said brackets. You didn't say "usually", you said "always".

This isn't a casual chat down at the corner pub. This is a technical discussion. We need to be technically correct when providing technical help to those seeking it.

Then, when I showed how your blanket statement was false, to include providing a link to a PC case fan that demonstrated you were incorrect, you still assert you were right - "unless" the product is marketed as a reverse fan. LOL.

What if the fan is no longer in the packaging - as seen here? Does your method work then? Nope!

Perhaps you are not aware that the products marketed as "PC case fans" are not used exclusively on computers. They are in fact, simple "box fans", the same used in many other electronics, but packaged in containers that say case fan on them. So you are correct to say that ceiling and window fans lack relevancy here in a computer tech site, but then you didn't specify "PC" case fans. And, of course, I also included a PC case fan to illustrate my point.

I did not put words on your keyboard. You made a blanket, "absolute statement". And like all blanket statements, it was wrong. And yes, I fully understand the irony of that blanket statement too.

The technical truth is that most case fans are designed so the air flows out the mount side of the fan's housing. However, since some do not, it is best to verify first. This is most easily done by looking for rotation and airflow direction arrows embossed on the housing. Or, if no arrows, by powering up the fan and feeling for air flow.

It was a simple mistake, Zack. No big deal. We "all" make them occasionally. We're "all" human. Or "most" of us are anyway! ;)
 
It's amazing how far people will go to avoid admitting they made a simple, no-big-deal, mistake. And instead of doing so, they just dig themselves in deeper. :kookoo:

No, you didn't specifically say "all fans in the world". You just implied that by saying, said, "fan motor mount brackets are always to the... ...exhaust side." You didn't say "most" brackets. You just said brackets. You didn't say "usually", you said "always".

This isn't a casual chat down at the corner pub. This is a technical discussion. We need to be technically correct when providing technical help to those seeking it.

Then, when I showed how your blanket statement was false, to include providing a link to a PC case fan that demonstrated you were incorrect, you still assert you were right - "unless" the product is marketed as a reverse fan. LOL.

What if the fan is no longer in the packaging - as seen here? Does your method work then? Nope!

Perhaps you are not aware that the products marketed as "PC case fans" are not used exclusively on computers. They are in fact, simple "box fans", the same used in many other electronics, but packaged in containers that say case fan on them. So you are correct to say that ceiling and window fans lack relevancy here in a computer tech site, but then you didn't specify "PC" case fans. And, of course, I also included a PC case fan to illustrate my point.

I did not put words on your keyboard. You made a blanket, "absolute statement". And like all blanket statements, it was wrong. And yes, I fully understand the irony of that blanket statement too.

The technical truth is that most case fans are designed so the air flows out the mount side of the fan's housing. However, since some do not, it is best to verify first. This is most easily done by looking for rotation and airflow direction arrows embossed on the housing. Or, if no arrows, by powering up the fan and feeling for air flow.

It was a simple mistake, Zack. No big deal. We "all" make them occasionally. We're "all" human. Or "most" of us are anyway! ;)
It's context - this thread is specifically discussing case fans, so a comment like 'they blow towards the frame' isn't relevant to how jet turbines work
 
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