I can get into Halo and start playing for a couple of minutes but eventually every time i get these lines on my screen, my speakers give me high pitched ring and i have turn my comp off
hrm...sounds very severe...it doesnt seem like a gfx card problem only...first thing I would try is to uninstall all sound and video drivers...as well as directX...
then reinstall all the above and see how the machine fares...it might be a heat related issue...as you play the game, the gfx card heats up and then craps out like u are seeing...is it OC'd at all? Beyond that i dont know what to think until you give us some more specs and system information.