Ok guys any one got any ideas i havent already tried!

my new radeon HD6870 has been installed it play bf3 like a dream no crashes no errors. as soon as i try to play a Call of duty game mainly MW3 it started to black screen regularly.  i did a sysem reinstall and it fixed the problem slight but now its freezes for 10 seconds and then black screens.

i have set game to native also but it still happens, any other hd 6870 users or other radeons with same issue on MW3 but working on other games without issue.