this is where the bourne comparison needs to come back into the discussion, because it depends who is doing the replacing.
I, my partner and my uncle had had three recent macbooks experience sudden unintended swamping, two with water one with red wine, charlie fixed them all.
The apple geniuses - james bond company men all - carefully removed the screws from my computer, reverently placing them in actual surgical kidney dishes, then looked at me with the practiced empathy on their young beautiful faces, shook their heads slowly without breaking eye contact and said 'logic board' - the macbook cancer diagnosis.
magic charlie is the bourne in this story. I met charlie at his office, a claustrophobic box on a suburban shopping strip, tobacco fogged, every horizontal surface except for a few stepping stones between charlie and the door fractalling out jagged piles of derelict dismembered macbooks, maybe about a thousand, in pieces, some with surprisingly brutal injuries, a fist sized whole though a 15 inch retina.
I was lucky to meet him, the shop had been open a year, he was planning on closing it down and working out of home. he got few walk in customers, the few that did seemed unsettled by his casual disemboweling of their pristine objects of beauty atop of a mound of incomplete repairs, crowded by ashtrays - most of them overflowing, some for screws.
Those people would leave to take their computers to apple licensed stores, who - in violation of licensing agreements, but in obedience with the imperative of profit - sent the work to charlie. He charged the same price either way.
If a macbook is atomic, charlie is a quarks man, I watched for about ten minutes until he kicked me out, as he scrounged chips from the racks of donor laptops, desoldering and re-soldering tiny components into the open heart of my machine. The only explanations he gave of the undertaking were when he pointed a chip on the logic board and said 'sound', then lifted the board to eye level, held at two diagonal corners in his finger tips, and slowly spun the board through a full rotation, then made eye contact for the one and only time and said 'keyboard'.
When I came back the shop was shut. For about a week no-one answered the phone. Then I got a message from a woman on my phone "your computer's ready". I dropped by charlie's, I wanted to speak with him a moment, to emote my awe and gratitude, he wasn't interested, he didn't look up. the woman, standing in one of the bare-floored stepping stones took my money, don't remember how much, but less than a hundred.
it worked and still does.