Hi, I have a dell u2713hm and at the moment my mbp mid-2010 15" can't display more than 1080p. I'm using mini-dp to dp and I used to get maximum resolution before. But this morning my computer froze in login screen and I restarted it. After that I only have 1080p. On my macbook air 2012 I can get max resolution by using the same cable. Is my gpu on my mbp dead?