If you're a GAMER then there's very few games that benefit from a better CPU than the i7-7700K anyway.
I've got an i7-3770K at 4.4GHz paired with a GTX1080. It's rare to have a CPU bottleneck running 2560x1440.
The main benefit from an i5/i7 8th gen CPU running at 5GHz would be for 1080p res gaming and even then click through and look at the 1080p and 1440p results for the five or so games here:
http://www.guru3d.com/articles_pages/intel_core_i7_8700k_processor_review,18.html
Most have little to no benefit above even a stock i7-7700K (use similar CPU as it's not listed).