Horizontal case airflow question.

[baronpork]

Hello, my first post, be gentle

I'm assembling an HTPC which will run i5 3570k (yeah, i know, overkill) in a fairly small HORIZONTAL case (it is a mini tower, but looks good on a side).
The case is a former home to HP Pavillion s5650uk slimsine PC, chucked out old blown out innards and replaced it with Gigabyte Ga-z77m-d3h motherboard, 2x4gb 1600 ddr3 and i5 3750k. CPU will be cooled by Arctic Freezer 11 low profile cooler. A little later will add Ati HD6670 card for some more graphical oomph...

So, here's the problem to solve.
I'm not sure at this point which way the cooler will move air, on or off the cpu. Depending on that i may need to consider general air direction in the case. I'm planning on cutting out an opening for a large slow and quiet (220mm) fan.

The whole PC will be stashed into enclosed space without doors, sorta like a media cabinet that i have here.

I dont have the parts besides the case at the moment, i'm in planning stage still (although cooler is already ordered). Still cont have the big fan, will adjust my plans according to advice, if i get any...

Case size is (apprx) 300mm wide x 100mm high and 400mm deep. uATX form factor mobo.

So, any advice ?

 

[nna2]

the cooler moves air down against the motherboard, and helps cool motherboard components like the VRM

i would keep it in an open space, or you run the risk of overheating, alteast keep the door open