I had that bug - 1 of many
And yup it was my graphics card settings, i think that went when i toggled anostropic filtering to off, though to be honest that was the least of my graphics probs at the time, a simple thing to do is reset all your graphics card settings to minimal then reload them 1 at time - restart game check rinse an repeat, I also did this with all my ingame settings, it takes about an hour but is well worth it.