I have low fps in league of legends on a decent pc

As the title says i have a pretty decent pc but my league of legends runs on 50 fps sometimes. i have tested alot like v-sync, driver updates, setting everything on low, fps cap, geforce experience. when i changed my graphics from low to high or medium i dont lose any fps either. these are my specs: CPU - AMD FX-8350 RAM - 16 GB GPU - NVIDIA® GeForce® GTX 960 4GB Hard Drives - samsung 250 GB SSD pls i need help