grey/bikes

[McNeil Racing]

hey guys well ive followed some of the tutorials done some changes to my graphics card 5770, and nothing is working. ive tried to downgrad from 10.7 to 10.4 and the downgrade doesnt stick onto my graphics card everytime i check if it worked i go back and see that it is still at 10.7 if anyone can help me would be great. im wanting to play this game really bad and havnt played it in 2 weeks ahaha thanks