Is a cutout necessary for aftermarket CPU cooler?

Nah

necessary?
no

But its really helpful tbqh familia

>>>/g/sqt

No, unless you're literally retarded.

>>59671916
it's never neccessary, it's just easier to install if you have one (you don't have to take the mobo out)

not every aftermarket cpu cooler has a backplate, some (usually cheaper and small models) have the same plastic latches like intel stock coolers, which can be applied from the front

my case has a huge ass cutout, yet the positioning on the gigabyte z170 is so stupid I still had to take out the mobo screws and lift it to put the backplate in place.