So, here's the problem, I'm running toribash in a 2003 pc and it's kinda difficult to handle with the lag(9 fps), tried cheat engine, set up the computer for the best performance and even downloaded a game booster but the problem still persist.

Can you help me about this?

Thank you in advance.

If you are playing with the minimum graphics and are getting lag, it's time to upgrade your computer.

Optimizing your software only gets you so far. Get some more RAM or a new video card.

Reduce the graphics that may help,