as of right this moment I run an R430 1U dell server, which is a dual socket server with 4 3.5 drive bays up front, averages about 90w. Just being a 1U enclosure and having those tiny fans it tends to get loud. Was looking into a 3U disk shelf as well, but have seen 40mm fans on the back of them. I have too many 40mm fans as it is, I don’t need to add more with more noise. I know a 2U or 3U server enclosure would have larger fans and be quieter, and if I get the same generation or newer, use the same or less power.