I am one of those unfortunate one's who got stuck with integrated ATI graphics before i switched over to linux. Needless to say, the graphics performace was HORRIBLE even using the propreitary driver option with mint. I remember i had read somewhere that there were new ATI drivers available and today i stumbled on this site:
This site will tell you which driver you need, let you download them and instructions on how to install them. I just finished deactivating the FGLRX and installing the correct driver recommended and downloaded thru that site and what a difference
thought this would be helpful to nOOb's like me who might not wanna wait till Mint 8 for the new drivers to be incorporated into the kernel.