Original post by: asle ,
Sorry but you cannot upgrade just the processor since it is soldered to the logic board. What you can do is to change the logic board to a faster one. I.ex. you have a A1278 late 2011 and all the logic boards share the same connectors and will fit. Apple has named the unibody pro 13" for model A1278 through several upgrades. This means technically all boards from this model will fit. But they often change the speaker assembly or cable position for the iSight or bluetooth connector so you would have to mess with those parts too if you i.ex. try to install a 2009 logic board in a 2011 A1278. If you got hold of a 2.8Ghz i7 logic board in the same production cycle (late 2011) it would fit. I did that several times. I got a 2010 2.4ghz i5 MBP A1286 and bought a used 2.66ghz i7 board that is running fine, everything fits fine.