Apple sucks, but part heaven save my wallet. Buy cheap spare parts with very well service.
27" iMac A1312 MC813LL/A Mid 2011 Logic Board 820-2828 639-2289 CPU NOT INCLUDED
board was ok and it works fine
I had added the logic board from a mid 2010 model and a CPU for the 2011 for our project. They noticed the mismatched items and reached out to us about the mis match. Time and money Saved A+++++
Great service, Fast shipment, Great packaging thank you