Graphics card is biggest factor in fps.
You won't be able to simply swap out your cpu because xeon chips use lga 2011 sockets.
Best bet would be upgrading to RX 5700(xt)/GTX 2070 (super) gpu (both 3x faster than your current gpu). Swapping out your cpu would require a new motherboard also. If you do take that route, I suggest 2600 or 3600 on a b450 mobo (cheaper yet powerful enough), but ultimately, the graphics card is biggest factor when it comes to fps