I need a mother board to change in my 11" (model 2011)

I don't know what you consider a "low price" there's one logic board for your machine in the parts catalogue. Google Shopping is your friend.

Once you find a board obtain the recommended tools... every job is easier when you use the proper tools. Study (not just read) the guide before you begin. Most problems occur when beginners tear connectors off the MLB because they pulled the wrong way, forgot to unlock or us a tool to lift the edges.

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