Floor mounted case fan

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BlueGTIguy
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Floor mounted case fan

Post by BlueGTIguy »

I have a no-name mid tower case with a provision for a 80mm front intake fan. The problem is, this fan location is mostly useless due to the restrictive path for air between the fan and the outside of the case (front side USB, headphone jacks are in the way). I don't want to get into relocating the USB/headphone jacks, and I'm not too keen on a side-mounted fan.

I happened to notice that there is a lot of unused real-estate on the floor of the case. Furthermore, the case sits on little feet that give it about 4-5mm of space above the floor/desk surface. I'm thinking that I could easily mount a big CFM 120mm intake fan on the floor with virtually no restriction. Anyone try anything like this? Comments, suggestions?

Thanks.
Wookie8662
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Post by Wookie8662 »

I've done that before.
Just make sure the case isn't sitting on carpet, or is in a place that it can act like a vacuum cleaner and collect dust.

It would be better to put an upper exhaust fan towards the back, if there is a provision for one, and just leave an air intake vent on the bottom of the case.
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len444
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Post by len444 »

4-5mm of space
might need to go higher, though the total area at the case perimeter might prove to be sufficient.

(l)(h)= A
(125mm+/-)(4mm)= 500mm^2


(pi)(d)= A

3.1415927(80mm)= 251mm^2

should work. not sure if there are compression/ friction problems that will reduce the effective area down, but when comparing to some of the crappy designed (ie restrictive) front intake provisions......

if you go to the hardware store, you'll probably find some rubber buttons with adhesive backing that can be applied to the bottom of the case to elevate it some more. go for a 120mm fan, as it will be quieter, and will push the opening towards the outside of the case. you basically can't have any cabling laying on the fan, which is more than likely why this hasn't caught on. i'd secure a piece of screening over the fan to help prevent any potential problems. :idea:
BlueGTIguy
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Post by BlueGTIguy »

Thanks for tips guys. As of now I have two 80mm upper-rear exhaust fans (in addition to the P/S fan), but no good intake setup. I do however have a 80mm intake fan in the factory location, but it's relatively useless, thus the purpose of this thread.

I figure I'll elevate the case a little more and use a filter to keep the dust bunnies out. I hadn't thought of protecting the topside of the fan; good point. I do think 120mm is the way to go, both in terms of CFM and noise levels. Thanks again for the tips.
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