So I installed this card http://www.newegg.com/Product/Product.aspx?Item=N82E16814102841 I installed everything from the file in the 4890 Post by Cindori, and used the official ATI power connectors. I am fully updated to 10.5.7. I rebooted tried the card and all I get is a Black screen and the fans run 100%. Ive tried slots 1 and 2 and the same results. Please help here i pulling my hair out!!