Answer to: New iMac 5k 2017 CPU is Upgradable?It could be done. Using an 8 gen I7 on H110 is possible now. And many articles claimed that 6 7 8 9 gen core CPU are compatible with each other’s socket. So, here is my guess: 1 If we need 8th 6core CPU installed, Some modification on the socket pins is necessary which is referred to some tutorials. 2 When Apple release new EFI to new coffee lake devices, can we transfer it back to this iMac? That all, may this be helpful.