Need some help with fans... again.

[Andrew_C1]

So, around the beginning of the year I started this endeavor to build my own pc which has been a blast and I'm really enjoying learning all this cool stuff and getting help from everyone on this website, but then there's fans. I, for some reason, can't seem to be able to understand all the terminology for these things like AF and 140mm or 120mm. When I started asking questions earlier in the year I was getting a lot of people angry because, much like the intake and outtake of air through the fans, the information went in one ear and out the other. Can someone please explain in layman's terms the fans I'm going to need for my s340 case (https://www.nzxt.com/products/s340-designed-by-razer-now-shipping)? I believe my plan was to have one 120mm AF and one 140mm AF case fan and then my H110i GTX 280mm CPU cooler. I was also going to get however many more fans I'd need for the case in LED.

 

[bitwright]

I have no idea what you mean by an AF case fan. I'd think you meant "air flow," but I've never seen someone use it that way.

There isn't really much terminology involved with case fans. Fan sizes are measured in millimeters. The bigger the fan, the more air it pushes, so a 140mm fan will push more air than a 120mm fan if both fans are going the same speed. Often larger fans will be set up to run slower though, as this results in less noise coming from the fan, with the larger size ensuring that enough air gets pushed through despite the slower speed.

You also want more fans blowing air into your case than blowing out of your case. This is often referred to as having positive (air) pressure, and it helps keep dust out of your case. Having more fans blowing air out forms a vacuum inside your case (referred to as "negative pressure"), which can cause dust to get pulled into your case.

The nzxt s340 has 4 fan slots (2 in front, 1 in rear, and 1 on top) and comes with 2 fans (1 in rear and 1 on top, most likely both blowing air out of the case). You should double check to make sure the H110i GTX will actually fit in the front of that case and leave you with enough room for your video card, etc, as the front of the case will be the only place you can mount it. If it fits, mount it so that it pulls air into the case. I would also set up the top fan to blow air in, as I'm not sure you'll get enough airflow over all your parts with just the fans in your H110i as intakes. The rear fan should be left as an exhaust fan, blowing hot air out of the case. There are no more fan slots beyond those 4, so you won't need to buy any more fans.

 

[Andrew_C1]

I have no idea what you mean by an AF case fan. I'd think you meant "air flow," but I've never seen someone use it that way.

There isn't really much terminology involved with case fans. Fan sizes are measured in millimeters. The bigger the fan, the more air it pushes, so a 140mm fan will push more air than a 120mm fan if both fans are going the same speed. Often larger fans will be set up to run slower though, as this results in less noise coming from the fan, with the larger size ensuring that enough air gets pushed through despite the slower speed.

You also want more fans blowing air into your case than blowing out of your case. This is often referred to as having positive (air) pressure, and it helps keep dust out of your case. Having more fans blowing air out forms a vacuum inside your case (referred to as "negative pressure"), which can cause dust to get pulled into your case.

The nzxt s340 has 4 fan slots (2 in front, 1 in rear, and 1 on top) and comes with 2 fans (1 in rear and 1 on top, most likely both blowing air out of the case). You should double check to make sure the H110i GTX will actually fit in the front of that case and leave you with enough room for your video card, etc, as the front of the case will be the only place you can mount it. If it fits, mount it so that it pulls air into the case. I would also set up the top fan to blow air in, as I'm not sure you'll get enough airflow over all your parts with just the fans in your H110i as intakes. The rear fan should be left as an exhaust fan, blowing hot air out of the case. There are no more fan slots beyond those 4, so you won't need to buy any more fans.

I think the 120mm and 140mm fans i was planning on buying were to replace the case fans because I hear they aren't that great. So I can switch fans around and it will reverse the air flow? I thought I would need to either buy an intake or exhaust fan. Can you just flip it over?

 

[bitwright]

There are not special intake or exhaust fans. All case fans suck air in from the spinning side and blow air out the side that doesn't spin (the side with the plastic supports). An intake fan is just a case fan set up to blow air into the case, and and exhaust fan is one set up to blow air out of the case. You can just flip a fan over to change an intake fan to an exhaust fan and vice versa.

 

[Andrew_C1]

There are not special intake or exhaust fans. All case fans suck air in from the spinning side and blow air out the side that doesn't spin (the side with the plastic supports). An intake fan is just a case fan set up to blow air into the case, and and exhaust fan is one set up to blow air out of the case. You can just flip a fan over to change an intake fan to an exhaust fan and vice versa.

Ok so as a final check, the 4 fans i'll need are the 2 case fans, and the 2 CPU cooler fans?

 

[bitwright]

There are not special intake or exhaust fans. All case fans suck air in from the spinning side and blow air out the side that doesn't spin (the side with the plastic supports). An intake fan is just a case fan set up to blow air into the case, and and exhaust fan is one set up to blow air out of the case. You can just flip a fan over to change an intake fan to an exhaust fan and vice versa.

Ok so as a final check, the 4 fans i'll need are the 2 case fans, and the 2 CPU cooler fans?

Yes. Both the cooler and the case come with fans, and you really shouldn't need to replace them unless you are looking for something quieter. The stock fans they come with are probably good enough. If you instist on replacing them though, the numbers you really need to look at are fan noise (measured in decibels - db) and fan air flow (measured in cubic feet per minute - CFM). You want less noise and more airflow.

 

[Andrew_C1]

There are not special intake or exhaust fans. All case fans suck air in from the spinning side and blow air out the side that doesn't spin (the side with the plastic supports). An intake fan is just a case fan set up to blow air into the case, and and exhaust fan is one set up to blow air out of the case. You can just flip a fan over to change an intake fan to an exhaust fan and vice versa.

Ok so as a final check, the 4 fans i'll need are the 2 case fans, and the 2 CPU cooler fans?

Yes. Both the cooler and the case come with fans, and you really shouldn't need to replace them unless you are looking for something quieter. The stock fans they come with are probably good enough. If you instist on replacing them though, the numbers you really need to look at are fan noise (measured in decibels - db) and fan air flow (measured in cubic feet per minute - CFM). You want less noise and more airflow.

The only reason I want to replace them is so I can get LED ones that look fancy.