Bottom mounted case fan. Necessary?

[unplanned bacon]

So a few days ago I upgraded some of the fans on my build (added 2 additional LED fans, replacing one of the stock fans and putting the other LED fan in an available space at the top of the case) and now have a spare stock case fan. I was thinking instead of throwing it out I could mount it to the floor of the case (preferably I'd like an LED fan there). I have an air filter supplied with the case, but I don't know how to fit it in the required position. Will a floor mounted fan do anything, and should I make it an exhaust fan or intake?

 

[vmem]

floor mounted case fan should always be intake, as it draws in cool air from the bottom underneath the case and blows it upward toward your exhaust fans on top. a well positioned fan on the bottom should lower your GPU temperatures significantly, but won't do much for your CPU.

 

[bfitzpatrick]

A floor mounted fan will add slight effects to cooling. The only problem is that it will still collect dust and dirt from the ground, even with the fan filter. I would suggest putting your computer on a table to reduce dust/dirt intake. Which way the fan is blowing is your opinion. If you want to blow kind-of cool air over your GPU/motherboard, than do so. If you want to take the heat out of your case, make it exhaust.

 

[sincreator]

Typically the front side and bottom fans are intake fans. The top and rear are exhaust fans. In most computer cases there is no bottom fan spot, so it's probably not neccesary. If you have a fan allready and want to populate that spot, then I advise having it as an intake fan.

 

[EasyLover]

Instead of putting it on floor better mount it on the side panel, it will be more effective and there will hardly be a dust/dirt issue. Though both options are not necessarily required. It would be rather more preferable if you mount it on top side to ensure the good push configuration (if you have space there).

 

[unplanned bacon]

Instead of putting it on floor better mount it on the side panel, it will be more effective and there will hardly be a dust/dirt issue. Though both options are not necessarily required. It would be rather more preferable if you mount it on top side to ensure the good push configuration (if you have space there).

Occupied and occupied. The side slots are occupied by stock fans and the top is occupied by one stock fan and the additional one I put. The only spare space is the bottom and I have a spare fan for it, because one of the stock fans was removed so I could put a new LED one in

 

[EasyLover]

Ok good enough. Put it there in push configuration and make sure that there is some space between the surface on which case is placed and the case itself otherwise it will be all good for nothing.

 

[unplanned bacon]

So, as an exhaust or have I got that hte wrong way?

 

[vmem]

put it in as intake. if you have it as exhaust it would be working against the natural flow of air. remember that warm air rises, so the general air-flow in your case will start with cool air from the front/side, the air getting warmed up, and getting spit out from the top and the back. having a bottom in-take fan helps with this general airflow, whereas having a bottom exhaust works against it.

also, look at your net intake/exhaust ratio. most traditional cases end up having a negative air-pressure vs atmosphere, ie there are more exhaust than intake fans. in this case, any crack/empty fan slot you have in your case will be sucking in air and dust to equalize the pressure difference created by your fans. by having more intake fans than exhaust, you fix this problem.

I have a bottom intake fan myself with a filter on it. and aside from wiping the filter every month or two, I have not had to vacuum/clean my case at all in over 2 years. and it still looks almost brand-new inside (there is no dust build up on my CPU and GPU heatsink fans)

 

[EasyLover]

So, as an exhaust or have I got that hte wrong way?

Sorry for late reply. Not in exhaust mode dear. It should push fresh air inside the case otherwise ventilation and air flow will be disturbed and you'll face heating problem. From front,side and bottom fresh air should come in and from top and back hot air should be thrown out of the case