Ideal place to put in a case fan to lower gpu temperture

[iPhilipz]

I currently have a Phantom 410 case. I have two exhaust fans, one in the rear, one at the top and One intake in the front.
See picture below.

The yellow boxes are places where I could put in more fans. The green arrows are where the fans are and which way the air is blowing.

My goal is to lower the temperature of my GPU. So I bought a 120mm fan and put it as a intake fan right where the yellow box that is right in the middle of the GPU. However after installing the fan, my temperatures did not lower at all. Not even 1c.

I was wondering where could I put a fan in my case that will help lower the temperature of my GPU.

 

[Karadjgne]

That looks like a blower style gpu, so mounting an intake fan on the bottom, blowing towards the gpu fan will offer the best results. I'd also put a 2nd 120mm in the front intake position.