I updated to the 1.9 patch , when loading all i see is the mouse cursor and hear the logo sounds in the background but everything else is a black screen but the game is working because i hear it.

my system specs are amd phenom x6 8 gigs of ram windows ultimate 64 bit and hd 6870

what could be the problem? I deleted it and reinstalled it but no use it works fine if i dont install the patch but after installing i get the black screen wtf?