Asus RS520-X5/PS8 - Manual (Page 56)

4-14 Chapter 4: Motherboard information
12. Parallel port connector (26-1 pin LPT1)
This connector is for a parallel port. Connect the parallel port module cable
to this connector, then install the module to a slot opening at the back of the
system chassis.
13. Serial General Purpose Input/Output connector (2x4 pin SGPIO2)
This connector is used for the SGPIO peripherals for the LSI Logic MPT
utility.