Would this work?

[EasonIDontKnowAnything]

Let's say I attach a computer system (motherboard and etc) to my wall. And I put a air conditioner on the opposite wall. ( room is small but not too small like just enough for a bed desk and etc.) Would it be enough to cool the system?

[3 Lions]

No 

[Princess Luna]

You need a CPU cooler whatever you do

[EasonIDontKnowAnything]

So basically a CPU cooler will always be needed.

[DocSwag]

Air is a horrible heat conductor so yeah, you'll need a CPU cooler unless you run a single core CPU at .8 ghz.

[Cyracus]

15 minutes ago, EasonIDontKnowAnything said:

So basically a CPU cooler will always be needed.

for the foreseeable future, yes also airflow is important in keeping your mobo and ram from getting hot enough to emit magic smoke or bursting into flame

[LogicalDrm]

22 hours ago, EasonIDontKnowAnything said:

So basically a CPU cooler will always be needed.

CPUs lid is very small surface area. Main purpose of CPU cooler is to make that surface area larger. More surface area, more heat can be transferred to air.

 

Could you run CPU cooler without fan, probably not. Look at test benches. Those are practically same thing. Just room air circulating around. And still they require some attached fans to improve natural airflow.