Which should I get for fortnite?
Ryzen 5 2600
The reason?
For Fortnite, it doesn't really matter which of the two you get for it.
The r5 2600 is much more geared towards gaming and brings better results to the table in this area. The ryzen 7 1700X is designed more for productivity.
Has a better single core performance, which is more important for gaming, and the 8 cores are quite unnecessary for gaming and especially for Fortnite
Since Fortnite really hardly has any CPU demands, almost everything is enough… So it doesn't really matter which of the two you buy… But I would rather recommend the R5 simply because it is cheaper… And is also more suitable for gaming
Both are not suitable for your target 200fps, but if then the 2600