high class gaming? standard gaming? or gaming with some multitasking or gaming with so much multitasking?
for gaming purpose only, i5 8600k is more than enough
standard gaming? i5 8400 / 8500 or r5 1600x or r7 1700x can do good
with some multitasking? same with above
hardcore multitasking? from r7 to threadripper then
which one?
since you asking only gaming, then i5 8600k is my recommend (going 8700k is likely overkill)