ASROCK Fatal1ty Z77 Performance Series User Manual page 26

Step 2. Connect two Radeon graphics cards by installing a CrossFire Bridge on
the CrossFire Bridge Interconnects on the top of the Radeon graphics
cards. (The CrossFire Bridge is provided with the graphics card you pur-
chase, not bundled with this motherboard. Please refer to your graphics
card vendor for details.)
CrossFire Bridge
Step 3. Connect the DVI monitor cable to the DVI connector on the Radeon graph-
ics card on PCIE1 slot. (You may use the DVI to D-Sub adapter to convert
the DVI connector to D-Sub interface, and then connect the D-Sub monitor
cable to the DVI to D-Sub adapter.)
or
26