You may not activate the win10, I think you can boot the PC, but if you had the i7 4790 ( Haswell Refresh ) the Z87 will need the newer BIOS to support the Haswell Refresh cpu. If you had the i7 4770, the Z87 will support the i7 4770 without updating the BIOS.I am afraid windows 10 will not start with mobo on different chipset.