My understanding is that a neutral air pressure inside the cabinet would take care of overheating. Air intakes and exhaust will have to be channeled through foam lined fins in order to absorb the noise. At least that's the concept I see most commonly in designs of other people. Or perhaps, something like this :
My concern with all these setups is the close proximity to the enclosure wall. We are dealing with high-temperature electronics - don't forget! You want cool air surrounding the whole unit ideally (safety first). My setup is attached and is based on a YouTube example I saw. Half a year in operation with 0 issues and I'm overclocking 20%ish (setting 444 for the Antminer owners) to maximize profits as things gradually lower.
