Turn the resolution to 800x600 and then lower the settings to the minimal. Check out the tweaks by low spec gamer.
Enjoy the 1000+ fps. It does make a difference. I mean your brain can never tell the difference between 1000+ or a 10000000000x10^10000000 fps even if the gap is big but your mind will be grateful to know your computer is outputting that many frames in one second.