Yosemite blue grey Screen O Death

i have a late model 2011 MacBook Pro, and I upgraded to Yosemite two weeks ago. Yesterday I was working in After Effects on some pretty big movie files when the laptop screen just went black. When I restart I get the apple coming up, then the thermometer shows for about a third of the way,mother the blue grey Screen O Death. I have reset the PRAM Tried starting in safe mode, same thing happens Tried starting with command D, same thing happens Tried starting with command, option D, got the terminal spewing out a bunch of tech stuff then went the the blue grey screen. Tried fsck, said nothing wrong Tried resetting the NVRAM, would not work, just went to blue grey screen. Tried starting with command S and emptied trash through the terminal. Tried rebuilding permissions in terminal, but was unable to as I was signed in as a single user. At one point, I held down the D key for a long time after it had begun to boot and was asked if I wanted to resume where I left off before the crash, and the system came back online, I said yes. Then started quitting programs and then it went black again, and I have tried to replicate all of this again and again. I don't understand how I can fix this with the Internet back up when I can't get this to start. It's like looking up a word in the dictionary to find it's meaning only to have them use the word to describe the word. It looks like the Mac Guys have finally figured out how to turn a Mac into a PC, using Yosemite.