Fan positioning for air 540

[Novirius]

Excuse me since I'll be typing this by voice detection. I have 5 fans I need to position them for positive pressure I can put two on the top two in the front and one in the back the bottom does not support a fan. In the past I put two intakes on the top and two intakes in the front in order to achieve positive pressure however I noticed that the top was dusty. If I put the top to an exhaust setup I think I will have negative pressure. Will having negative pressure by changing the top to an exhaust create more dust than having the top being intake. The top has poor dust filtering.

 

[Valantar]

What case are you using? Is it a regular "single chamber" setup? And what kind of hardware do you have inside? What size are you fans - are they all the same model/size? In general, five fans is verging on overkill for most computers, going past the point where more air gets you noticeable cooling benefits, all the while creating more noise. If I were you (and your setup isn't something like an ultra-OCd X99 or AM3 platform with dual/tri SLI/Crossfire - i.e. pulling 800W+ under load), I'd step down to four fans - two intakes at the front, one exhaust in the rear and one in the top. I'd then adjust the setup so that the exhaust fans run slightly (~20-30%) slower than the intakes - either by using some sort of voltage limiter wire or controlling it through the BIOS/motherboard software.

The main point of positive pressure is to avoid dust being pulled in through cracks and openings in the case, while at the same time making sure all coolers always have sufficient airflow. Overdoing it doesn't make any real difference. Keep the fifth fan as a backup or for some other use.


Edit: damn, I had this thread open from this morning, and forgot that the case was in the topic title. I take it all your fans are 140mm? If not, the front takes three 120mm fans. Still, I stand by my advice for the 2+2 setup.

 

[UsandThem]

I believe this is the case they have:

http://www.corsair.com/en-us/carbide-series-air-540-high-airflow-atx-cube-case

Fan Mount Locations
Front: (x3) 120mm or (x2) 140mm
Top: (x2) 120/140mm
Rear: (x1) 120/140mm

On my system set-up for positive pressure, I have three Nocuta intakes ( 3 x 140mm @ 700-750 RPM) and one 140mm @ 780-850 RPM exhaust. I have a Fractal Design R5, so when I have my front door closed on it, I don't hear my intakes (or my exhaust for that matter) unless I lean down towards it.

But if you want to run an additional exhaust fan on the top of the case, you will just need to balance out your other fans to make sure air is coming in faster than it is being exhausted.

 

[Novirius]

I'm back on PC now, sorry for the poorly worded post. I have an Air 540 and five 140mm fans. Currently, I have two running in the front with my Kraken x61 (Intake) and one in the rear (Exhaust). I also have a blower type GPU. I have two intake fans installed at the top of my PC, but I turned them off. I think the Kraken only supports two 140mm fans, so I doubt it would hold three 120mm.

Previously, I had two intakes running at the top, but the Air 540 is missing dust filters at the top and I was unsure how good the DEMCiflex dust filters were. I want to avoid cleaning out as much dust as I did this time around.

I know that I can control fan speed, but is there a way to control is proportionally? For example, having the top two fans run at 30% of the speed of the front fans? Since the front fans change with CPU temperature, I want to avoid a situation where the front fans slow down and the top/rear stay at maximum speed.

 

[UsandThem]

I know that I can control fan speed, but is there a way to control is proportionally? For example, having the top two fans run at 30% of the speed of the front fans? Since the front fans change with CPU temperature, I want to avoid a situation where the front fans slow down and the top/rear stay at maximum speed.

You'll just have to play around with your set-up, as they are all different: Different fans, temps, environment, etc.

Just monitor what RPMs your front fans do from idle to load, and adjust accordingly. Maybe you only need one rear exhaust, and one top exhaust instead of two up there. Maybe move your AIO cooler to the top. Because it will be tough to create positive air flow with four exhaust fans (1 rear, 2 top, and PSU) with only two intakes. You can always always buy those dust filters and use the tops as intakes, but then you will have crazy positive pressure unless you run some at low RPMs.

 

[Novirius]

Sounds like a plan, thanks.

 

[UsandThem]

Sounds like a plan, thanks.

I spent around 2 hours changing my fans around and changing the RPM until I got it where I had positive pressure and it was quiet enough for my liking. After you change yours, check inside your case for dust, and if there is new dust in there, just tweak your fans a little more until you get to the point where you only need to blow your case out like once a year. Good luck!

 

[Valantar]

Mentioning that two of the fans are on a radiator would have been useful right off the bat - it changes a lot. Radiators introduce significant resistance to airflow, reducing the effect of the fans significantly even at high speed. If that's your setup, I'd move the rad to the top of the case (exhaust), run a third exhaust in the back at a low RPM, and have two front intakes at whatever speed is necessary to achieve positive pressure. Get some incense sticks if you want to make sure you have positive pressure, they make for handy smoke testers. Just light one, and hold it close to any openings without fans in them - if the smoke gets pushed away, you have positive pressure, if it gets sucked in you have negative pressure, and if it just dissipates, you have neutral pressure.

 

[Novirius]

That's a neat trick.

 

[MrTeal]

There is a lot of honeycomb on the rear of the Air 540, along with vented PCIe blanks and the bottom being open. With a blower style GPU, I'd be surprised if you really even needed an exhaust fan.
I haven't played too much with my Air 540 recently, but IIRC the top is much easier to get off than the front. You need to remove two little screws to remove the front after the top comes off, while the top is just a couple thumb screws.

I would considering running a couple really slow intake fans one the front, through the filter. Place the Kraken on the top, with the rad on top and the fans on the inside of the case drawing air through the radiator. You want to be able to just pop the top off easily, as 90% of the cleaning you're going to be doing is lifting the top and vacuuming the top of the rad.