will this cpu bottleneck the system?

^^Yeah Hitman is another one that responds to more than four cores/threads, meaning an 8th-gen i5 or 7th-gen i7. You can see that here where the i5 6600K sits in the mix with a GTX 1080 test bed (add about 5-8% for improvement over the 6600K with the 7600K which is not tested here):

http://www.guru3d.com/articles_pages/intel_core_i5_8600k_processor_review,18.html

Older test of an i5 7600K here with a GTX 1080 where it stacks up against i7s:

http://www.guru3d.com/articles_pages/core_i5_7600k_processor_review_desktop_kaby_lake,15.html
 

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