Chosen Solution
I have a friend who’s willing to give me his 2015 15” MacBook Pro Retina. It’s the one with two GPUs (the Intel and the AMD). The logic board is fried (three beeps on boot) so it needs replacement. Do I need to get the exact same board? Don’t seem to see many of those on eBay, or at insane prices. Can I install a logic board that only has the Intel graphics? I know it would be a loss of graphic power, but the price difference is big. Also, does the 2015 only take a 2015 logic board? It was the year Apple added the force-touch trackpad to the MBP line and I know for a fact that the logic boards of the 13” 2014 and 2015 are different: the trackpad connector is bigger, making a swap impossible. Is this the same thing on the 15” MBP?
Sadly you’re between a rock and a hard place. You can’t use older logic boards (remember this is the last system before the newer Touch bar & Fn models). The reason the prices are so high has to do with the demand and availability of this series logic boards. The DG boards are highly sought! As far as going with the IG board thats a possible solution. While IFIXIT is currently out of stock I would recommend you post a notification so when shows up you have a chance: MacBook Pro 15" Retina (Mid 2015, Dual Graphics) 2.5 GHz Logic BoardMacBook Pro 15" Retina (Mid 2015, Dual Graphics) 2.8 GHz Logic BoardMacBook Pro 15" Retina (Mid 2015, Integrated Graphics) 2.2 GHz 16 GB RAM Logic BoardMacBook Pro 15" Retina (Mid 2015, Integrated Graphics) 2.8 GHz 16 GB RAM Logic Board You’ll also need the proper heat sink for the IG model if you go that way.
