Asus P5WD2-E Premium - Manual (Page 159)

A S U S P 5 W D 2 - E P r e m i u m A S U S P 5 W D 2 - E P r e m i u m A S U S P 5 W D 2 - E P r e m i u m A S U S P 5 W D 2 - E P r e m i u m A S U S P 5 W D 2 - E P r e m i u m 6 - 3 6 - 3 6 - 3 6 - 3 6 - 3
3. Insert the CrossFire™-ready (Slave) graphics card into the PCI Express
x16 black slot. Make sure that the card is properly seated on the slot.
4. Connect an auxiliary power source from the power supply to the
graphics cards.