lag/fps

Now i have a pc with a problem no matter the settings be it low high or ultra all same fps on every game why, can someone pls help me is it the bottleneck i dont get it. My PC :CPU RYZEN 3 1200 3.1 GHZ GPU RX 580 SAPPHIRE NITRO 4GB RAM 16GB 2666MHZ 2X8 KIT...