I've got a box fan in the window pushing air out, and 2 box fans behind the rigs pushing air through them. I thought it might help to have the small fans in front to try and pull air through the cards like the setup on this veddha frame. It's fluctuating between  90° and  100° F where I live and the cards on my bottom rig are running a little warmer than I would like.

https://i.ebayimg.com/images/g/3M8AAOSwZHRgAQiw/s-l640.jpg

Does anybody know what they use on this frame to run those fans?

I'm going to try another box fan and set it up to push cooler air (from a room with air conditioning) into the rig room. Hopefully that will help. I have 10 of these small fans with Molex connectors and just thought it might help. It seems like fans can have 3-pin, 4-pin, molex etc connectors, making it more challenging to find the solution.

Thanks for the suggestions.