Answer to "replaced battery, no longer reporting state of charge correctly"I would try doing a couple soft resets (Hold power and home button), and if that doesn't work, try putting the original battery back into the phone and then soft resetting. It could just be a bad new battery, but worst case it could be the tristar chip on the logic board.
Answer to "Is it possible to change the factory i7 with a Skylake i7?"From what I am reading, the iMacs use odd socket sizes (FCLGA 1156) and that through some experimentation, one user tried upgrading his i7 to a better one of the same socket size, but it would not boot. I don't believe Apple has any firmware restrictions that would prevent you from upgrading, but I think the issue came down to it not providing enough wattage to the new CPU. Here's an fairly detailed article on the CPU's of your particular line of iMac. http://www.everymac.com/systems/apple/im...-aluminum-faq/imac-intel-aluminum-processor-upgrade-instructions.html