Asus P5N-T Deluxe - Manual (Page 163)

ASUS P5N-T Deluxe 6-3
2. Insert the first graphics card into the PCIEX16_1 slot (blue), the second into
the PCIEX16_2 slot (black), and the third into the PCIEX16_3 slot (blue).
Make sure that the cards are properly seated on the slots.
3. Align and firmly insert the 3-way SLI bridge connector to the goldfingers on
each graphics card. Make sure that the connector is firmly in place.
3-way SLI bridge connector