Chosen Solution

Hi. To explain the best. The laptop had a GPU problem. So I changed Logic board. Also I changed RAM And HDD to a ssd. Worked fine for a week.. And Then red lines. Never had that problem. Comes to the loading Apple logo. And Then turn dark Grey without the red lines. It wont Boot to safe mode, recovery mode or diagnostics. please help! Tried resetting SMC And everything. Update (08/21/2018) I havent tried a external monitor. It wont do any diagnostics When i Boot it up.. on the normal screen

The 2011 boards all suffer from the same GPU plague. The replacement GPUs or replacement boards are just used or refurbished boards waiting to fail. That’s because there are hardly any replacement GPU chips to repair the boards in a lasting manner. My advise is to stop sinking money in it. At this date. I expect all of them to die sooner than later. Alternatively, you can send back the board for a refund, and invest in a 2012 board. That one will need a soldering technician to replace the LCD connector on the board - to allow a 2011 screen to connect to a 2012 board. But it is pretty straightforward if they know what they’re doing.

Someone had solved the problem, so I’d like to see if this method is still helpful. Thank you! Connect to an external monitor. If you see the same lines on that screen it points to a VGU/VGC (logic board) problem.The heat and fans lead me to think this may be what’s going on but best to connect to an external monitor to confirm or deny that supposition. If the external screen looks normal it would point to an internal video chain problem. Run AHT test 2 or 3 times to see what problems it finds. Record any error messages it reports - come back here with them.