Does fan position really make a massive difference? - Hardware & Software

Hey so I recently got a new case. It has a nice little window in the top for a fan overview. Right now I've got 2 fans installed in the top, but they're intake along with my 2 front ones. I was wondering if this would cause a massive issue with my PC's temperatures, as I really don't want to flip them, since the LEDs won't show. My setup: https://files.facepunch.com/forum/upload/134123/d3c2e8d5-bcdb-43de-9d55-71d57af445cb/image0.jpg

It does make a decent difference, but your setup with intake on the front and top and exhaust at the rear is a pretty common and desirable positive pressure setup. It'll help slow dust buildup too.

Are those huge-ass 20cm fans in the front? As it is, you've got a ton of airflow going in and almost no place where air can escape out of the case. Best case scenario, those top fans are a total waste of effort, and actively working against you at worst. Flipping them around would be ideal. If you want a lightshow in your PC you can always get some extra LED strips.

It shouldn't really be working against him at all, that case has plenty of mesh and gaps that any additional air pressure will just be forced out them instead of dragging dusty ass air in from the ground. Especially with that rad grabbing air from inside the case I'd much rather have strong positive pressure than negative.

There's a reason why people usually set up their intake fans on the front and bottom and exhausts on the back and top. That way you draw in cool air on one side, have a simple and straightforward path for the flow to take over your components, and once it heats up it takes pretty much the shortest way out of the case on the other side. It's hard to know for sure without testing, but I imagine OP's setup would cause some weird airflow patterns. Sure the air will find its way out of the case through the gaps somehow, but is it really a good thing if the top fans are working against a huge positive pressure so that their flow might just immediately get redirected right back through those gaps at the top? That being said, that fan setup is total overkill for the amount heat OP's pc produces. You could probably adequately cool a heavily overclocked multi-gpu system with that stuff. So I imagine the temps will be fine either way. At least do what Lolkork said, turn up the speed of the back exhaust fan and reduce the speed of all intakes to a minimum, that way you'll have a somewhat more balanced pressure situation.

An intake top rad is an extremely common thing though? The top fans are usually what you want to switch depending on what kind of pressure system you want to obtain in a case. I do agree that turning some of those fans down is a good idea, those 200mm monsters move a lot of air.

I can see the reasoning with a top mounted rad if you want to pull cold air directly over it. But OP just has two fans as intakes for no good reason other than wanting to see the lightshow. It creates a massively imbalanced setup that most likely won't help with cooling as well as it could.

I really don't think putting two exhaust fans right before the radiator intake is going to help either though.

Yeah it's hard to tell how exactly the airflow behaves inside the case without a way to simulate or visualize it, but it can still help if you think about where the hotspots in your setup are and how you're gonna blow that hot air out of the case. In most cases the hot areas are gonna be like this: https://files.facepunch.com/forum/upload/209687/01c34395-0fb3-4aa0-bb2c-7d308ae94129/1.png Or if you have a watercooling setup like OP https://files.facepunch.com/forum/upload/209687/6c1ca92e-3e74-443e-841e-b219a5815206/2.png When you look at his fan setup, it doesn't look that bad at first glance, it gets the air to where it needs to be: https://files.facepunch.com/forum/upload/209687/414507d6-db2e-4013-8bff-088fa051ac7e/3.png The massive overpressure could be a problem though. You can just sort of hope that most of the air will get bruteforced through the holes at the back of the case and that it won't cause any weird turbulences. My guess is that this setup would work just as well if you took both the top fans away, and you end up with a quieter system. As you said, turning both top fans into exhausts might not be such a good idea: https://files.facepunch.com/forum/upload/209687/a22fc6f2-c695-47ba-b10d-d3157cec905e/4.png One of them is basically useless cause it just redirects the intake air straight out of the case. The one towards the back might still help pulling heat away from the graphics card area. Maybe one in, one out would be a little better: https://files.facepunch.com/forum/upload/209687/d2ad1c19-2902-449e-a8aa-1c3e7dbd51ba/5.png You still have all the heat building up at the back of the case though, and you're still running an overkill number of fans. Something like this might be more optimal: https://files.facepunch.com/forum/upload/209687/46f439c8-2152-49f1-9721-7833db6280df/6.png Put the rad on the top blowing out and it gets a dedicated stream of fresh air just for itself, so it doesn't need to draw in air that's already been heated up by the GPU. The GPU area also gets plenty of ventilation. Honestly I'd just put the rad on the top and one exhaust fan at the back, and get rid of the other top fan. That way you still keep a decent positive pressure without going totally overkill. And there's still a ton of airflow where you need it so you can easily run the case fans at low RPMs.