I think this should compare well with the 1080p 144Hz gamer at
https://www.reddit.com/r/PCMasterRace/wiki/builds#wiki_144_fps_ultra_build
1. CPU compare:
https://cpu.userbenchmark.com/Compare/Intel-Core-i5-6600K-vs-AMD-Ryzen-5-3600/3503vs4040 shows the AMD ahead but it has more cores but still in the game.
2. GPU compare:
https://gpu.userbenchmark.com/Compare/Nvidia-GTX-1070-vs-AMD-RX-5700/3609vs4046 shows the 1070 just a notch behind.
So this is solid 1080p gamer which will deliver 60 FPS on almost all the games.
Hope this helps.
PS. I should have compared it to https://www.reddit.com/r/PCMasterRace/wiki/builds#wiki_60_fps_ultra_build
I'm looking at a PC with an Intel i5-6600k cpu, gtx 1070 8gb, and a Gigabyte Z170N Gaming 5 mb. Is the processor good for gaming and the specs good too, for games like, gta v, battlefield, fortntie, apex, big games like that?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic