In your card you have SPDIF IN and GND.
On your mainboard you have +5V, SPDIF OUT, GND. (I honestly don't see the SPDIF header in specification of the board you given nor while looking at its picture).
Use multimeter to find out which pin is +5V and which one is GND.
On most mainboards they are aligned as follows: +5V, free space, SPDIF, GND
On graphics card pin marked with two little arrows is SPDIF IN.