Hi all, I have a cooler master cm 690 ll case (Not Advance).
I want to add a fan behind the CPU on mother board.
What size fan could I get for the small vent behind the CPU.
Would I have that fan pulling air in or pushing it out?
80mm in that mount.
You'd have to experiment what yeilds best temps.
I'd probably use it as an intake if you have any vrms on the back of your mobo.
I have that case and have never felt any need to add a fan there.
Best additions to that case for cooling are 2x140mm top exhaust and a 120mm on back of hdd cage for gpu cooling.