Fan rpms and airflow

[Brasdos]

Hi I’m planning on building a pc and I’m wondering about case fans and airflow. If I were to put 3 fans as exhast spinning at 1600 rpm and 2 intake at 2400 rpm, will I get neutral/positive pressure? Note that each fan is rated at 44cfm and 74cfm respectively. Also will the psu fan affect airflow?

[Firewrath9]

you would have negative airflow by 16 CFM. as for your second question, no

[Imbellis]

The PSU fan would affect airflow - I've seen some rated for up to 40 CFM; however, this balancing airflow isn't too important - I'd just generally try to go slightly positive.

[wONKEyeYEs]

36 minutes ago, Brasdos said:

Also will the psu fan affect airflow?

Depends if the intake for the PSU draws from outside the case or inside.

[EsaT]

Those advertised airflows likely aren't true anyway.

But you would get lots of noise from such high speed fans.

 

What case you're looking to get?

[Brasdos]

1 hour ago, EsaT said:

Those advertised airflows likely aren't true anyway.

But you would get lots of noise from such high speed fans.

 

What case you're looking to get?

Corsair carbide spec 06

[airdeano]

2 hours ago, Firewrath9 said:

you would have negative airflow by 16 CFM. as for your second question, no

prolly even more as the air filter is going to restrict the overall input of air into the case.

[WoodenMarker]

The airflow is greatly affected by any obstructions in the way including mesh / filters. It's hard to tell how the airflow will turn out for sure. If you're aiming for positive airflow, it's best to overcompensate with something along the lines of 2 : 1 for intake : exhaust.

The psu may or may not affect overall case airflow depending on whether or not it's isolated from the rest of the system

What are the system specs?