Plutonium

[GOD] Sebas having 2 antiviruses isn't the smartest thing, I remember running Malwarebytes and Avast on old rig, and it was overheating a lot. Remove one of those, and try cleaning your PC from trash files. Some antiviruses in general affect PC performance, while some constantly block Plutonium (which is why you need to add it to exclusions list), and that tutorial can be found here https://plutonium.pw/docs/antivirus/
To uncap FPS, you have to type the command in in-game console (which is accessed via button under Esc), and then type com_maxfps 1000 (or any maximum number allowed).