I just downloaded Halo the trial version and installed it. But when I launched the game it it said that my video card has not been tested. Also when I got to the mission my character kept side steping to the left. Then when I wanted to exit the game I moved my cursor over the circle of the ok button it high lighted the circle white. Then it high lighted the cancel button and it switchs back and forth I do have service pack 2 and Direct X 9.0c.
Well, Ive heard that Service Pack 2 sucks, that it is full of errors, and conflicts with alot of games and programs. Im sticking with Service Pack 1 for now. Although I dont really know how to help you, I dont know much about technical issues, maybe someone else here can help you.
-Sirius- maybe someone else here can help you.