A server auxiliary operating system is disclosed, which includes a case, a plurality of swappable GPUs and a printed circuit back plane. The case includes a bottom board and a first mounting bay located at the front portion of the case. The swappable GPUs are disposed in the first mounting bay. The printed circuit back plane is disposed on the bottom board and has a plurality of first interfaces and a plurality of second interfaces electrically corresponding to the first interfaces, wherein the swappable GPUs are respectively coupled to the first interfaces, and the servers are respectively electrically connected to the corresponding swappable GPUs through the second interfaces respectively connected to the servers so as to expand the server operation capability.