Responder a: Upgrading to a1229/1261 logicboard?Hello. The difference in the Model numbers determines the type of processor in the logic board. For example I too have an A1212 17" MacBook Pro, BUT mine was produced in the earlier part of January 2007, so it is NOT able to accept El Capitan. I'n going to have to upgrade the logic board to the ones made with the Santa Rosa processor which is the 2.44Ghz one. There are 2 logic boards that will fit the A1212 and the differences are either the i5 or i7 processor. This would DEFINITELY benefit you in regards to being able to the latest Apple OS. You wouldn't be stuck running Mac OS X Mountain Lion 10.7.5 in other words. I just found this all out today after calling Apple to inquire about why my MacBook Pro A1212 wouldn't download El Capitan. I'm going to swap the logic boards out myself. It's pretty starightforward and there plenty of videos to coach you along the way. I hope this helps! You're gonna look for model numbers A1229 & A1261 for the compatible logic boards that will fit your A1212.