Interesting that the Terraminer used 48V and good choice as it lessens the strain on the buck mosfets (lower currents) and allows for thinner copper power planes up to the bucks. I rather assume miners have moved to using 12v mainly as a legacy thing from early miners like the s1 and others which were easily powered from small ATX supplies. Now is mainly because of that legacy and the abundant supply of multi-kw server-grade 12v PSU's. At least the string topo now used keeps currents to a reasonable level though.
bah I actually linked the wrong version of the correct PSU.
The cointerra is a PET1300-12-054NA
The exact same PSU but 12v. I still have a few floating around here.