Some enterprising hardware enthusiasts have proven Intel's claim that Coffee Lake can only run on the Z370 chipset, even thought the pins physically match, to be somewhat less than accurate.  There are some limitations which stem from the difference in power draw, the basis of Intel's reasoning for the incompatibility.  The modders who made this work would not suggest trying to use an i5 or i7 chip, only an i3 as the power draw is not so far out of spec.  This is more of a proof of concept mod, it is not recommended you pick up a Coffee Lake CPU to slap into an older board as your main machine.  If you are curious how this was achieved you can drop by The Inquirer for more details.

"Through considerable tweaking and time, some modders posted on the Overclock forum that they'd managed to coax a Coffee Lake CPU to run on Z270 and Z170 socket-based motherboards, when its only supposed to work on Intel's Z370 chipset."

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