Ok so, up until recently when I discovered the "Frame Limiter" option in both games, i've been playing at the locked fps which I think is like 21. I first disabled frame limiter in San Andreas when I was in a server that reminded me that I could do so (I had no idea I could). So when I set the fps limit to 100, my game looked absolutely beautiful, so smooth, and fast, and alive. It made the game so much more than I knew it could be. However, ever since I disabled frame limiter, or set the fpslimit to 100, my character seems to sprint, AND swim, in absolute slow motion. I first noticed it when i was at the pirate ship and was trying to swim away, my character wasn't even moving, while I was tapping sprint, he was swimming fast, with the animation and everything, except he was just staying in one spot, so I ultimately died. I didn't think anything of it, until I played Vice City, and disabled frame limiter, and the game also ran beautiful EXCEPT, for crazy weird graphical happenings. For instance, the ocean water animation, went at the speed of light, the water went,and flowed as if life was in fast forward, and so did the fly's that are in the air near the beach, they were spinning around in circles at the speed of light, along with the water fountain near the amunation, it was spilling water out into the street so fast I knew there was a problem. I also could not reverse in any car. The car would make a noise, but would not go backwards, it would just sit there. The scene loading times for the missions were unbelievable. A black screen would show for about 5 minutes before the scene would actually play. So I knew something was wrong. I decided to enable frame limiter, and when I did so, the game looked so shitty it made me cringe, but all of the graphical problems stopped, and I could reverse/drive normally, and the cutscenes were back to normal. That's when I knew something was up. I tried setting my processor affinity to just 1 core, for vice city, to see if maybe the game was being over powered, although I know nothing about this. It didnt do anything and I still had problems. Vice City will not let me change the resolution or color depth, and it is set at 800x600 x16. So I set my resolution to 800x600 and set the color depth to 16, and the game was even more extreme with the problems (the ocean went by even faster). So I went into my Nvidia control panel, and browsed for Vice City's main .exe and opened it, and set graphical options for the game, such as texture filtering, and vertical sync, and etc, and so when I went back to the game, everything was absolutely perfect. The game still ran beautiful with amazing fps, there was no graphical glitches like the water/bug/fountain/fire/weather animations going at light speed, all the cars reversed and drove perfect, and the cutscenes loaded instantly, with absolutely no lag at all.
I have no idea if any of these things apply to you, but for me, as somebody who has been playing these games on the default locked fps, of 21, which is absolutely garbage, this was definitely a problem for me, and now that it's fixed I can finally enjoy these games.
Thank god I figured it out before I came on here crying to you guys about it.