Hi, you have to add 4 to 7 fans

and close the box.
I updated my post

- I have all 7 fans installed and I tried with the case both open and closed. Noise is the biggest concern to me, it needs to be quiet enough to have under my desk and not disturb anyone else around. If that means being able to only use 3 GPUs, that's fine, but I think there's an IRQ issue or something? - because the cards work, but only if at least 2 cards are sandwiched close together

- that's the problem I'm trying to solve.