Modularized redundant server PSUs are usually built this way: the modules are 12v only, and dumb as bricks, with the 3.3v and 5v supplied by the PSU's backplane

Modularized redundant server PSUs are usually built this way: the modules are 12v only, and dumb as bricks, with the 3.3v and 5v supplied by the PSU's backplane; unfortunately, this leads to server failure because of backplane failure. Some SAS backplanes for cases that fit a bunch of drives sometimes have their own 5v VRMs and take only a standard 12v connector of some sort. Helps when PSUs typically don't supply enough 5v to feed a few dozen drives, but supply more than enough 12v.