A question for gpu fixers/repairers

[Filip64]

So,i have my laptop which is now healthy and working its a macbook a1342..
Eventually my dad made it out of 2 macbooks like this one,desoldering and soldering on a lot of components from one board to another and eventually the board he worked on is now working.
So my dad had a healthy gpu from the other board and he soldered it on to this one,not reflowing it or anything like that,so the question is:
If i desolder a healthy gpu from one board and solder it to another will gaming with it kill it?

 

[hang-the-9]

If it heats up and breaks the home-done connections or overheats the video card, then yes it can die from gaming. No way to know really in your situation.