Looking for advice on setting up computer case fans
I've never actually put in more fans than what a case comes with, but I have an unraid server that is running hot so I got a pack of 5 fans to put in it.
From what I understand, you want them set up so that there is a solid airflow throughout the case; ie I'm planning to set it up so that the front and bottom fans are intake and the top and back fans are exhaust, so that cool air enters from the front/bottom and exits out the back/top.
However, one of the fans will be going on the side door. I'm assuming this wants to be intake as well (so that the airflow goes through the entire case, as I assume it would disrupt the airflow as exhaust). Or would it be better to not have one on the side and just have an extra fan laying about?
This is how I plan to set it up (shout out to MS Paint): https://ibb.co/KcXx5cgW
Note: The X's are because the installed chassis block being able to put fans there; the bottom one is especially disappointing as it's the HDDs that are mostly getting hot
Just wanted to confirm that that set up looks good and that intake for the side one (where the ? is) is the proper choice
Yeah, I'd say you would probably want the side fan to be intake. The general rule of thumb is that you always want more fans pushing air in then you have pulling out.
The only alternate layout would be to turn the right-most exhaust on the top to an intake and then have the side fan as exhaust. This will put the general airflow a more consistent right-to-left flow. If there is a built-in dust filter on the top (but not the side), then I would definitely go that route, instead.
For anyone interested in why, it's so you don't create negative air pressure inside the case which will cause air (and dust) to get sucked in from every tiny air gap in said case... which makes it get dirtier faster, and it can also be a PITA to clean out when dust accumulates in tight/inaccessible spots. So you want the opposite of that, slightly positive air pressure inside the case so air is steadily pushed out of the gaps.
In that same vein, I'll typically throw air filters on all my intakes. Usually front/bottom. Then put the exhaust back/top. The goal is to have almost perfect balance when all fans are in full jet engine mode.
Then fan curves are adjusted so that intakes always hit full bore faster than the exhaust. Usually means one intake is always on around 30%, the others are off until temps start climbing. They'll kick on basically in sound order, such that the rig is as quiet as possible for as long as possible. Something like all fans are on low, then intakes hit 100% faster than exhaust, and all go to max on the order of 88C.
I try to leave the side as a passive exhaust, good for testing if you have positive pressure. If a thin piece of tissue sticks to it, need to adjust those fan curves.
There is no dust filter on either the side or top (there are filters on the bottom and front)
But something that did occur to me - and I don't know why I wasn't thinking about it - is that I don't actually have anything installed in the top-right chassis and can remove it to have access to 3 top fans. And from what you're saying of right-to-left, it does sound like that would be a better choice. So that would look like this instead (case came with 2 fans [top front and back], so will have 7 fans total):
https://ibb.co/Z6r3zVwS
Thank you!
I'd also say intake, if for no other than it appears it's in a perfect spot to supply cool air to the CPU cooler.