I was thinking about changing my gamer tag name to something else. but will it affect my beta save for gears of war 3?
No not at all. Although I don't think the beta rewards are tied to your HDD save. They are probably tied to your windows live account which stays the same if you change your gt.
Nothing to worry about.
Beta rewards are tied to your beta game saves so do not mess with those. You can change your GT all you want and you will not mess anything up.
[quote user="Lord Dirt"]