https://cpu.userbenchmark.com/SpeedTest/2227/IntelR-CoreTM-i3-2120-CPU---330GHz
this is your CPU. No matter what kind of gpu you pair it with your gonna have serious bottleneck issues from your CPU which will not allow your GPU to even perform at half its actual performance. so if you persay got yourself the king of GPUS the 1080ti you would still see extreme frame drops when anything happens on screen due to your CPU
any triple AAA tittle will struggle to play using that cpu unless your playing less intesnive games like league of legends WOW counter strike etc. multi core speed is way to low to play new intensive games smoothly. id recomend a cpu that at least hits 400 in multi core minumum for newer games.
with that being said if your on a low budget look up some new CPUS and GPUS on offerup and letgo you could find a combo of both for extremly cheap vs store price