top fans for bitfenix prodigy mini-ITX case exhause or intake?

[okino]

ok so, for my prodigy mini-ITX case, there's the default front bottom fan that comes with the case, and I am installing a corsair H75 push-pull on the back top above the motherboard, but then I feel bad cuz the top of the case has place for two 120mm fans, so I will get those, but should they exhaust air out like the H75 or should they take air in from the outside? and should they be SP or AF fans, does it matter when they're not on a radiator? thanks

 

[Thaisnang]

Top fans are recommended to be used as exhaust fans but you can change it according to your needs. They can both be used as exhaust or intake, you just have to flip them.

 

[okino]

Top fans are recommended to be used as exhaust fans but you can change it according to your needs. They can both be used as exhaust or intake, you just have to flip them.

I know I can change their configuration by flipping them yeah, but thanks for the answer on it being recommended to be used as exhaust I am gonna do that then cheers and, does it matter if they are SP or AF?

 

[Thaisnang]

Top fans are recommended to be used as exhaust fans but you can change it according to your needs. They can both be used as exhaust or intake, you just have to flip them.

I know I can change their configuration by flipping them yeah, but thanks for the answer on it being recommended to be used as exhaust I am gonna do that then cheers and, does it matter if they are SP or AF?

I always recommend AF for case fans and SP for rads and heatsinks. In an open environment like most of the case fans have, AF would performs abit better than SP I think.

 

[Rammy]

Short answer - neither.

Top fans are almost exclusively exhaust locations, there are very few exceptions to this.
In a Prodigy however, your front-most top fan (let's call it TOP1) is positioned in front of your motherboard and is mainly going to exhaust air which has just been brought in from the front (without it heating up at all). This means it's at best pointless and at worst it'll have a negative effect on temps due to less cool air getting to the motherboard area.
The rear-most top fan (let's call it TOP2) is slightly more interesting in that it does have potential to add airflow/cooling. The difference is that in most cases it sits perpendicular to the motherboard, rather than parallel. This means it's a lot further away so there is no direct flow from VRMs etc or the ability to pull air from between heatsink fins. You can add a fan here, but in my (limited) testing - it does nothing but add noise. There might be some configurations which benefit from TOP2 (obviously if you are running a 240mm rad you might use this anyway) but these are going to be fairly niche.

The biggest improvements to cooling in a Prodigy are replacing the front+back fans with better ones. The Spectre fans which come supplied are pretty quiet but don't move much air and the front fan has a poor location for airflow. If you are using a closed loop cooler then the rear fan gets removed anyway so it's not a significant concern here. For the front fan, any upgrade in size (140/200/230mm) gets you a much better, central fan location which blows straight across the motherboard rather than against the HDD cages.

To address your SP/AF question. It's not one with an obvious answer. The easy answer is "AF for case and SP for rad/heatsink" but both types of fan have both properties and the greater the resistance (whether it's a dust filter/mesh etc) will gradually increase the viability of higher static pressure fans.

 

[okino]

Short answer - neither.

Top fans are almost exclusively exhaust locations, there are very few exceptions to this.
In a Prodigy however, your front-most top fan (let's call it TOP1) is positioned in front of your motherboard and is mainly going to exhaust air which has just been brought in from the front (without it heating up at all). This means it's at best pointless and at worst it'll have a negative effect on temps due to less cool air getting to the motherboard area.
The rear-most top fan (let's call it TOP2) is slightly more interesting in that it does have potential to add airflow/cooling. The difference is that in most cases it sits perpendicular to the motherboard, rather than parallel. This means it's a lot further away so there is no direct flow from VRMs etc or the ability to pull air from between heatsink fins. You can add a fan here, but in my (limited) testing - it does nothing but add noise. There might be some configurations which benefit from TOP2 (obviously if you are running a 240mm rad you might use this anyway) but these are going to be fairly niche.

The biggest improvements to cooling in a Prodigy are replacing the front+back fans with better ones. The Spectre fans which come supplied are pretty quiet but don't move much air and the front fan has a poor location for airflow. If you are using a closed loop cooler then the rear fan gets removed anyway so it's not a significant concern here. For the front fan, any upgrade in size (140/200/230mm) gets you a much better, central fan location which blows straight across the motherboard rather than against the HDD cages.

To address your SP/AF question. It's not one with an obvious answer. The easy answer is "AF for case and SP for rad/heatsink" but both types of fan have both properties and the greater the resistance (whether it's a dust filter/mesh etc) will gradually increase the viability of higher static pressure fans.

First of all, thanks so much for the detailed answer!!

oh and I guess I didn't mention that I am replacing the front 120mm fan that comes with the case with a 200mm BitFenix Spectre Pro so I am glad you brought this up so the 200mm specture in the front is gonna push air towards the mobo right? and it's a shame to hear that two exhaust fans in the top won't make much difference, but you see, cuz of my H75 I remove the back top fan, and for my 200mm spectre i am removing the front bottom fan, so now I have two fans left for me to do with as I like, and it's not like I am paying money for two new fans you know, so then you mention it might actually negatively affect the temps ? would it actually be better if the top didn't have any fans at all then and should I keep those two fans as backup then? cheers