need help w/case cooling

I'm looking to find a way to cool my system efficiently and i need some suggestions.

the case i have is this:
http://www.xoxide.com/x-aviator-case-black.html

i have 3 of these fans to add to the chassis:
http://www.xoxide.com/quad-white-led-80mm.html

I was wondering if it is ever a good idea to have cool air blowing in from outside the case. (kinda like having cold air induction on my civic) would it be good to have a flow from outside blowing in, then another fan (on the side of the case) blowing exhaust?

the only problem i can think of is dust.

you'd be best having an extra intake, as this will lessen the pressure on the exhaust if my knowlege of (admittedly basic) physics serves me right, and therefore lower noise slightly. The biggest benifit will be interms of temps, the more cold air you have in your pc usually the better.

Hope this helps

Dave

2 fans on the front, 1 on the back, nearer to your cpu's heatsink is better... that'll create back pressure at the same time drawing out the heated air around your CPU.. its common for heat to build up around poorly ventilated CPU's.