Intel I7 fit I5 motherboard

Solution
All that matters is if the socket is the same as the processor have the right BIOS version.
The exception is the new Intel 8xxx processors need a z370 board.
an example, the intel i5 6600 and i5 8600 both need a motherboard with a LGA 1151. there are motherboards with 170Z, 270Z, and 370Z series chip sets. the i5 6600 will work with a motherboard that has either a 170 or 270 chip set but the i5 8600 only works with the 370Z chipset
 

bignastyid

Titan
Moderator
Mainstream boards(socket 115x) support celerons, pentiums, i3s, i5s and i7s(sockets and chipsets do have to be compatible).

With enthusiast level boards socket 1366, 2011, 2011-3 use i7s, Socket 2066 uses i7s, the new i9s, and 1 model of i5(the i5-7640X). Sounds to me like you have an enthusiast board. Some of these also support certain Xeons cpus.
 


Indeed, it might confuse.
So, the golden rule would be:
Z170 boards work with 6th gen CPUs and 7th gen CPUs after a BIOS update
Z270 boards work with both 6th gen and 7th gen Intel CPus, no matter the BIOS
Z370 boards work with 8th gen CPUs only.