Problem with Video in MBP Late 2011

Hello,

Since last month I am having problems with my MBP, I thought it was due the thunderbolt display but it shows the same problem working without any periferal.

The problem is green/blue vertical bars in screen and the machine gets completely freeze. I need to manually shutdown. Additionally sometimes it does not start and it only shows a gray screen.

I went to service support and they replaced the hard disk and logic board but the issue is still present, yesterday I pick it up again from support service (2nd time) and they have no idea what they are doing (I live in Panama so I have no access to apple official support service but authorized ones)

I attached the system log when it displayed the problem.

OSX: 10.9.4
MBP: Late 2011 8,2
Somebody knows what could be?

Thanks in advance

Alejandro

View attachment systemlog.txt

I just read through the error dump. It looks like GPU failure (Graphics processor) but I can't tell for sure. You really need to have Apple run their diagnostics to be positive. However, the symptoms you describe and also the error log indicate GPU problems. Are you sure they replaced the logic board with a new one? The graphics processor is soldered to the logic board which does require the entire board to be replaced. But it appears like you have the same problem.