max frame rate is tied to your monitor. if the refresh rate is 60 then you will be capped to 60, unless you disable vsync and you will see a number higher than 60 but the monitor will still only do a max of 60.semp
1-4.
I'm get anywhere from 80 up to 130 with Hi-Res on my nvidia GTX 550 ti.I've heard that you don't notice a difference after 60, but when the new version first came out I dropped to 60-70 FR and I did see a significant difference.