Thank you for the reply.
Just to make sure I understand correctly, you need to replace the Mainboard (AV Board), on one of the TV's and are wondering if they use the same part number board, is that correct?
No, the Mainboard for the LE40C580, will not work with the LE40C530. The correct part number for the 530 is: BN41-01536A. This board is showing as Out Of Stock at the only source I could locate it:
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