How should I mount my 120mm aio?

[Brandonscott4]

Ok so I was wondering what is the best orientation for a 120mm aio for the lowest cpu temps possible. I have space to mount it at the top, the rear or the front (preferably not the front as it is only a 120mm aio). I know that temps are usually significantly cooler when the cooler is pulling in fresh air so could I have it as an intake in the rear or on the top?
Here’s how I have It positioned right now-

 

[SpyderTracks]

As PCS sell custom desktops and laptops we can’t advise on self builds or competitor builds, you may want to check out toms hardware which is an open forum