Once you purchased the qualified AMD Hardware during the AMD Promotional time span and you received the Game Code or Coupon from your Retailer you need to go here to redeem it from AMD: https://www.amdrewards.com/
NOTE: You must have the qualified AMD Hardware installed on your computer before redeeming the Game code or coupon. AMD will have you download a small Verifier program to check if you have the AMD Hardware installed and if it is the correct AMD Hardware for the AMD Promotion.
