For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
Get a DDR3 memory slot tester to see if any data lines are broken. Although at this point I'm suspecting a bad CPU. What rework station did you use to change the GPU?
It was a Chinese cheapo station here belongs to a friend of a friend. So you think it might have burnt the CPU? I'll look for a mem slot tester.
I'm not familar with CPU replacement on these macbooks. I also dont see any for sale using the part number off this board. Is this a bad avenue to go down? Time for board replacement?
You destroyed a $600 board with a garbage rework station. When I have a machine with an unrepairable board it is end of the line. No way these machines are worth spending $600 on a board. Dump the whole thing on Ebay and cut your losses. Next time take stuff to Apple