For getting good FPS in the game, you need to do the best graphics settings in GTA 3 definitive edition according to your PC, If you have a low-end PC, then you need to do different graphics settings in the same way if you have a high-end PC then you need to set different graphics setting for getting very nice FPS. The older version of this game runs smoother on any platform but in the latest version of GTA 3. ie GTA 3 definitive edition,you need a high-end PC if you want to play smoother with high graphics.
Best Graphics Setting for High end PC
if you have a good PC, I mean to say, if you have a high-end PC, then you can set this setting, Just watch this video which I have given below and follow the same for getting more FPS in GTA 3 definitive edition.
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Best Graphics Settings for Low end PC
if you have a low-end PC, then try to set this setting in the video which I have given below. Just follow the video and do the same as the video.