Problem with GTA 5

Hi! I have problems with FPSOs. After installation and launch, the game automatically put the settings on high. In the end I was around 40-50 FPS. But I'm somehow not enough and I decided to put settings on standard. In the end, nothing has changed. The same 40-45 FPS, and sometimes less. And yet my task Manager shows full load on the CPU and the video card has almost no load. How to be? Help.
PC:
Ryzen AMD FX-4300 Quad Qore 4.20 Ghz
1050ti 4 gb
8 gb Ram