Here is the GTA 3 definitive edition lag fix method, you can apply this method in your game if you want to play GTA 3 definitive edition on your low-end PC with good FPS.
The old version of the GTA 3 game can easily run in the Low-end PC even at high graphics settings, but the definitive edition of the GTA 3 game requires a better PC if you want to play smoothly in high graphics. Suppose you have configured a high graphics setting in your game and you have a low-end PC, then you can’t run GTA 3 definitive edition game smoothly on your PC. So in this condition, you have to change graphics settings for playing Smoothly even on a low-end PC, Now simply you have to watch the below video and follow same like this video because, in the video, every step is given for configuring graphics and other things for fixing the lag problem in GTA 3 definitive edition.
In order to Fix lag in GTA 3 definitive edition, you have to do some graphics settings and some copy-paste processes, all those steps are in the below video.