Hey everyone, I have a big problem with my late 2011 MacBook Pro. The computer just locks up at every click and then reacts. My bootcamp partition works fine, and I don't see any abnormal CPU consumption. I already did a clean install of Yosemite. But the computer still has the same issue preventing me from upgrading to El Cap. I am really running out of ideas, do you have any suggestions. PS: I don't have another mac so I cannot create install media.