I want to set up my shelf of rigs in the garage as it is beginning to overwhelm my office.
I am in FL, and my garage gets as hot as it gets outside. Would an ambient air intake of 100F be able to keep 20ish GPUs cool so long as I keep air moving across them and exhausted out?
You are probably going to want to pull air in from the outside and from below the height of the GPUs then exhaust it back to the outside above the GPUs.
To figure out how powerful of a fan you will need, plug in the heat load in Watts (basically the at-the-wall power consumption) and the temperature rise, delta-T, in degrees Celsius (assume 20-30C) into this equation:
CFM = (1.756 * Watts) / (delta-T)
So, for example, 2000 W with a 20 C temp rise allowed will require a minimum of 175 CFM. That's the ideal case, of course.
Apologies for the mixing of Imperial and Metric units, but using degrees F makes the equation cumbersome while converting from cubic meters / second to CFM is relatively easy.