im using my 5850 but im encountering a driver problem, after installation of driver my screen flicker then will hang and appear a message says something about the driver is not compatible to my card,but i used sapphire refference edition and i try the latest driver and also try another 2 kinds of driver from defferent version but still the problem occurs,but when im using my card without driver install the problem didn,t appear, and the card runs at normal,still i can play my fav games without affecting the performance,is there any cure about this problem?And if it cannot be resolve,is it ok to use my card without a driver installed?