Guys when there is group-fighting my PC always lag and my FPS drops to 30-40

[910829929]

I choose the FASTEST video setting,but my FPS always just below 80. I5-9600,RTX2070,16 RAM,here is my configuration。

 

[BGRT]

CPU bottleneck I guess, on low + fsr2 quality settings 21:9 monitor mine doing around 100-160 and 60~ in heavy fights. RTX 2060 + 5800X3D