Nice setup.. have a small 120 GPU setup that i had running in a spare bedroom.. I was venting hot air out via a maxair 24 inch fan..  HOA required i move my rigs to an area where they could not be heard.. Have moved it to the garage for now.. Heat is my biggest problem.. cant drill holes in the walls..

Planning on opening a door from the garage partially and making an additional screen door and mounting an exhaust on it.. how loud are the QuietCool AFG PRO-3.0 Attic Gable Fan Model fans (Red ones)

How many have you or others had to use ?

Also most of the PSU are the HP Server PSU.. they are super efficient, each 1200watt (@220V or 900W @110V) is powering 4 gpus (Rx570/ Rx580) as long as ambient temp is under 87F they work great.. any higher the PSU are like jet engines ! i have just 24 of these and they are the main reason for all of the noise

... any idea how to isolate or reduce the noise.. dont want to buy new PSUs..