I have one of the 2011 15" MBP's that have had its Graphic card repaired on the extende warranty Apple offered a couple of years ago. However, recently it started to show various lines and stuff, when working in Photoshop and Indesign. A restart, and it worked good again.
And so came yesterday... I was doing some work and the screen suddenly got dark. I heard it working though, and after a while it went to sleep but it refudsed to wake up. So I did a hard reset, and first thing on the built in screen horizontal lines show up (photo attached)...
The progress bar shows up though, but after a while the computer shuts down, or eventualy stops with a grey background with no more progress.
- When the grey background shows, the lines disappears.
- When I start in terminal mode, the line disappears.
- I am *not* able to start in recovery mode or on a Sierra or High Sierra start USB.
- I *am* able to start in target mode (with lines still showing).
- I have backups on iCloud Drive and on local drives, and I can reach all files on Target mode, so no worries there.
So. To me it seems like parts of the graphic card works. Maybe the internal card works, but not the external?
Is there any chance to rescue this machine? I was waiting for the next generation of MBP (2018), so it would be great if I could do something to have it work some more months... Since I can start in terminal mode I should be able to alter some settings on the GPU(s), but I don't have the skillset for such work.
All help and ideas appreciated!

And so came yesterday... I was doing some work and the screen suddenly got dark. I heard it working though, and after a while it went to sleep but it refudsed to wake up. So I did a hard reset, and first thing on the built in screen horizontal lines show up (photo attached)...
The progress bar shows up though, but after a while the computer shuts down, or eventualy stops with a grey background with no more progress.
- When the grey background shows, the lines disappears.
- When I start in terminal mode, the line disappears.
- I am *not* able to start in recovery mode or on a Sierra or High Sierra start USB.
- I *am* able to start in target mode (with lines still showing).
- I have backups on iCloud Drive and on local drives, and I can reach all files on Target mode, so no worries there.
So. To me it seems like parts of the graphic card works. Maybe the internal card works, but not the external?
Is there any chance to rescue this machine? I was waiting for the next generation of MBP (2018), so it would be great if I could do something to have it work some more months... Since I can start in terminal mode I should be able to alter some settings on the GPU(s), but I don't have the skillset for such work.
All help and ideas appreciated!