I have two 1600xt XGE 512mb PCIe that i want to crossfire. The mother board i have is a ECS P965T-A [info: http://www.ecsusa.com/ECSWebSite/Products/ProductsDetail.aspx?detailid=681&DetailName=Specification&MenuID=44&LanID=9 ] According to my research, i have to enable crossfire in the bios, but how do i do that?