You can even go with i3 9th gen.............i use it with my 1660 oc
if you are poor buy the i5 9600kf and a second hand gtx 1060 3 or 6gb, it will be a well balanced system. with worse cpu and bigger gpu you wont be able to use all of the gpu even in modern games
buy an i9 9900k and youre good
take in consideration that i5-9400 has no graphic card.
lol i have a i5-7th gen and gonna buy 1660(not super ) too ,so i think your choice itself is the best or else the amd one,but i heard that most games run better in intel cpu althought amd are cheaper and better ,idk if its true ,check benchmarks ,i think your choice is good.
i just now saw about i5 - 9400f and realized how stupid i am,my 7th gen has inbuilt gpu so its priced higher than the 9th gen ,when i bought i was not thinking of buying a gpu ,now i realized my mistake ,please dont buy a processor with integrated gpu man ,its useless
intel all the way
ryzen is overrated