So, AMD is celebrating its 50th anniversary with some promo gifts when buying certain AMD products. You can get 2 free games and a free t-shirt. Here are the processes: 
T-Shirt

1. Buy a AMD Ryzen 7 2700X 50th Anniversary Edition
2. In the Ryzen 7 2700X CPU package you find a small card with a code. 
3. You can redeem this directly on the amdrewards.com page

The Gamebundle

1. AMD Ryzen 7 2700X 50th Anniversary Edition
2. Request a Voucher from the shop
3. Go to amdrewards.com and create an account
4. Receive the confirmation mail and activate your account
5. Redeem the voucher
6. Download, install and run the "AMD Product Verification Tool" (no idea if they have a Linux version)
7. You get three "credits" and put the 3 games @ 1 credit each in your basket, confirm order
8. Get an Ubisoft's Usuck activate link for "The divison 2"
9. Get two codes for Epic's "Exclusives suck" Shop