I googled it , I was curious myself. A evga tech answers it at evga boards.https://www.evga.com/forums/tm.aspx?m=15540&mpage=1#15645Correct, all EVGA X58 boards support Crossfire.
This applies to x58 and 1156 boards. Not older nvidia chipset boards.
Also crossfire support in some of these boards DOES NOT mean sli support.
But as I originally stated, Evga SLI x58 +1156 boards support ati crossfire in those same slots.