That board has two PCI express slots, but is not SLI compatable.
http://www.neoseeker.com/Articles/Ha...ultralp/1.html
this review on Page 2 states what the intention is. It is to allow up to 4 displays to be used by utilizing to PCIe cards. But it is not SLI compatible.
edit: if you want a good SLI board and you can return that one, get the Asus A8N series, provided that you still want to stay with skt 939. That is an awesome board!