FPS issue is worse and worse every match - not related to PC specs nor software

I literally had 36 fps 99% of the game today. For a second I thought that It may be 12 chrome tabs open that cause it, but of course that was not the issue and I should know it is not since I can run even 30 chrome tabs and play other games with usual high FPS. Closing game client didnt work. I even recently reinstalled lol, hexrepaired it and reinstalled graphic drivers in hope that maybe for once its not riot fault. Well my hope vanished. capping fps at 60 and 80 was bugged for a long time. You never get fps cap. You get stutter 56 fps with this set up. Any other cap doesnt work either. I used to have over 300 fps.

Let me also say that issue persists no matter what graphic settings I use in game nor in graphic driver. This issue is not bad PC or laggish software. Riot screwed up again after last patch and I'm seriously getting done with this bullsht. I saw streamers and other people getting same problems yet riot refuses to answer ever on technical issues that I remember were REPORTED FOR OVER HALF A YEAR ALREADY IF NOT MORE. FFS I USED TO HAVE 120 STABLE FPS ON OLD 10 YEARS OLD MACHINE. Riot you screwed up something and you MUST fix it.