SMC Issue

Hi all,

I'm having a rather strange issue....

I have a 13" MBP early 2011. Not too long ago, the GPU was replaced by a 15" MBP graphics chip.

Here is the issue:

I have tried this several times. I have installed a fresh copy of High Sierra and Sierra (tried both). When on battery, the Macbook starts and shuts down perfectly. There are no issues with the display and all is working perfectly. When it comes to the time when I charge it. When I plug in the charger, it seems fine but once i restart it or shut it down, the Macbook will not start without resetting the SMC. This takes several attempts and sometimes results in me needing to disconnect the battery. Then, once I get it to start, the screen flickers, as if the GPU is not working. This stays like this until I reinstall the OS in which case the Macbook is fine again, until I connect the charger. Also, the screen flicker issue only happens with MacOS, tried linux and windows and there was no issue.

My question is:

Is this a hardware or software issue? I know it obviously stems from hardware but it may also be apple software simply not accepting changes, which might be fixable with a patched kext?

Looking forward to hearing what you think!

Dave