Custom case airflow

[InertiaSelling]

Hi, I'm planning to rebuild my computer in a smaller, custom case, but I havr no idea which fan setup would provide the best airflow. Here's a quick drawing of the project (though I will probably use a riser and install the graphics card horizontally)

 

Spoiler

 

I have two 120mm fans from my cooler master masterbox 5. Should I

1 - put both of them at the front of the case (which will sit horizontally) and cut a passive exhaust vent at the back

2 - do the opposite (passive intake, two exhaust fans) 

3 - put one at the front, the other at the back

4 - buy (or make) a pwm splitter and an extra fan so that I can install two intake fans on one header, and still have an exhaust fan at the back.

 

Thanks.

[emosun]

The only thing that matters is this

so long as the air thats in the case is going out and new air is coming in , that's all that matters. So long as the individual componenets (cpu , gpu , power supply ect...) are not reusing the hot air they make to cool themselves off , then they will be fine.