Should the door fan on the case blow in or out?

[chazzeromus]

I have a shorter than normal ATX case I've been recently cleaning out everything and oiling fans. And I wondering, would it be more efficient to have the door fan blow onto the motherboard? If so, wouldn't there be a risk for a lot more dust build up?

 

[DoomsWord89]

You could purchase a fan filter, that should take care of the dust should you choose to install it as an intake.

I suggest that you simply try both intake and exhaust and see which gives you the best results.

 

[leonkennedy_7]

using a side door fan as intake or exhaust depends on ur case and gpu. some gpu exhaust the hot ait through the side and some exhaust the hotair out side case through the vents above or below the IO panel. for those cards which exhaust air in case through the heatsink vent its better to have a side door fan as exhaust and at the same side u should have a fan on the case floor to intake the cool air or if not that u should have a powerful front intake .

for the cards that dont exhaust air in the case you can have the side door as an intake

you can check where ur card exhausts hot air by holding a piece of paper

 

[chazzeromus]

Oh yeah it's a server computer so there aren't any cards with internal exhaust. But I only have the fan for the door, so I guess blowing in is my best bet?

 

[ahnilated]

Yes, blowing in is your best case. I have another more worrying question though. I hope these fans that you are oiling are ball bearing type fans.

 

[inzone]

If you only have the one fan then you would want to get the hot air out of the case and by having it as an exaust then the intake will come from what ever vents you have , but you do want to have the fan blowing out. Is there any way to add another fan so you can have one blowing in and one blowing out.

 

[inzone]

Just reread you first post and you said you were oiling fans and then later in another post you said you only had the one side fan so , do you only have the one fan.

 

[chazzeromus]

Oh no, I have one front intake and one exhaust in the back. I also have no expansion slot covers, so it seems like most the intaked air would escape and wouldn't fully permeate, so I thought it'd be a good idea that have the air blowing in. But no I do not have another fan to add to the door.

 

[chazzeromus]

Nevermind, I got a new fan and tested with it blowing in, then blowing out. Blowing out seems to be the best, keeping a constant flow of air is better for carrying warm air out seems be the reason I suppose. I was getting temperatures of 45 - 48 C idle with the air blowing inward, blowing outward the temperatures ranged 42 - 45 C. I suppose I should get my expansion slots covered though.

 

[chazzeromus]

Best answer selected by chazzeromus.