Case cooling fan DUST!!

[DoPeFiSh]

I have a NZXT case and 3 case fans (one in back, one on the clear side, and one in front)......as of now they are all blowing outward, I suppose to suck heat out and there's not much dust inside the case, but If I was to flip the fans to suck in (especially the front fan to blow over all the hard drives) I would get LOTS of dust inside the case and all over the CPU, is there somekinda filter I could get or should I just let them all blow outward?? Not to mention that if I was to get a filter it would probably block all my pretty fan LEDs

thanks

[pwborders]

If you have them all blowing out then the dust is coming in somewhere else, often the floppy or other open type drives. The only difference is if the front fan is very low and the case sits on the floor, then it picks up dust really well. In the case of a low front fan you either put a filter on it for intake use or only use it for exhaust as you are now. What you might want to try is leaving the front fan as exhaust and change the other two to intake. That would lead to a back to front aitflow, except for the power supply fan, that might keep the drives cooler but would mean hot air from the front of the case.

In my setup (below) I have the front and side fans intake and the rear and PS fans exhaust. Keeps the drives nice and cool and the side fans are right over the PVR cards keeping them cool. The case I have also has a duct to the side for the CPU that does a good job of keeping it cool as well. Everything is very quiet too since they are all 120mm fans.

If you need filter material go to your local big box store (walmart kmart etc) and get the foam filters that are sold for window air conditioners. Very thin foam that can easily be cut to fit your fan. Mounting is up to you, whatever you use make it easy to take on and off since you will need to clean the filter once a month or so.

[DoPeFiSh]

I had lots of dust from the side fan when i got the case that fan was intake so everything got dusty fast including the cpu (not good) then I flipped that fan to exhaust, so now all the fans are exhaust, I'm wondering if its bad to have all the fans exhaust? I dont want to fry something........

thanks

[David]

I had lots of dust from the side fan when i got the case that fan was intake so everything got dusty fast including the cpu (not good) then I flipped that fan to exhaust, so now all the fans are exhaust, I'm wondering if its bad to have all the fans exhaust? I dont want to fry something........

If all the fans are trying to pull the air out of the case and air can not get into the case, the difference in air pressure will keep the fans from pulling air out and it will get too hot. Most cases have enough ventilation that this is probably not an issue.

[Chris.Day]

You should really aim to have some kind of airflow path through the case so that all components are cooled. Outside air comes in one end (usually the front), warm air comes out the other (usually the back).

In my system I have the rear exhaust which is thermally controlled (Nexus 120mm, idles at around 500RPM, goes up to 1000RPM under load), and the power supply fan. I have an Athlon64 3200+ with a Scythe Ninja, and the exhaust fan produces enough airflow through the Ninja to keep it cool (35°C idle, 55°C load) without a fan on the CPU heatsink. There is no chance of doing this (safely) with something like a P4 Prescott for example so it all depends on your individual system.

Generally, you do not need side fans, or even the front fan for that matter. There are some exceptions to these rules though.

The front fan may be useful if you have a very restrictive intake. In this case a fan can help to force air into the case. I use the Evercase ECE-4252 which has a very open intake, and so can get away without using a fan. There must still be good airflow in my case even without this fan, since my two 7200RPM hard drives barely go over 35°C.

In a lot of cases side fans can be determental to good cooling (due to disrupting the airflow), except for CPUs where you need really good cooling (e.g. P4 Prescott again) and the side duct lines up with the CPU properly.

As for dust. You can minimise that by taping up all gaps around things like optical drives and floppy drives (although the floppy drives themselves always seem to be good at sucking up dust) and then using filters on the air intakes (which you must then keep clean).

[nitrogen_widget]

Another thing to keep in mind is wire routing.
the tighter your wires are the better the air flow.
I use wire loom where I can & fold IDE cables up & use cable ties to keep them round when I don't have actual round cables available.

I've noticed that with good airflow I get more dust behind the PC & on the exhaust fan than inside the PC & this tell me a good portion of the dust that gets sucked in gets blown right back out.

Also a blowhole fan installed on top of a tower case makes a big difference for case tempuratures.
Not as big a difference as a side fan blowing on the cpu though as other's pointed out.

[DoPeFiSh]

the furnace filter works AWESOMELY!!!!! no dust inside yet!!