It's not the TS3 program that is the deciding factor on where to cap frame rates, it's your monitor. If you have a 60 Hz monitor/screen, than any frames per second above 60 fps your monitor cannot interpret and they are the equivalent of digital noise being generated for no useful purpose. If you have a 120 Hz or higher monitor, then the frame rate can be safely capped at such a higher rate.
Most flat screen monitors sold in the US are 60 Hz, even the high end Apple ones (or whatever brand they are selling today) for high precision video editing. Game enthusiasts will seek out those with higher refresh rates and the markets in some countries seem to have settled on 75 Hz as the standard for casual use for whatever reason, hence some differences.
The issue with TS3 in particular is that like other games of its development era it has no functional built-in fps limiter and the higher end video cards being sold today can run wild on it, generating fps in the many hundreds or thousands. Besides being horrible for game performance and leading to graphics glitches, lag, screen tears, and crashes, this is potentially harmful to the system and can burn its components out if left unfixed.
