Late 2011 MacBook Pro logic board upgrade

I have a 2011 MBP with a 17” monitor. Everything works great, except for the Radeon GPU which prevents the computer from booting up. I found coding that allows me to bypass the GPU and use the internal intel GPU, however, it still has issues on a regular basis. Is there a logic board I can upgrade to that has a more reliable GPU, not the Radeon HD 6770M? If I had a 13” or 15” I would not worry about it, but since you can’t buy the 17” any longer I would really like to keep this one working.