gui miner gpu problem

[froika]

i have installed gui miner on windows 7 with sappire 7750 1gb and amd 8core 4ghz.the problem is gui miner can find my gpu so now im mining only with my cpu (116 mhash). i have not installed open cl. do i have to install it in order to mine with my gpu? where to download it? what do i have to change about the drivers?.thanks